{ "instance": { "a2020q2form10-qdocument.htm": { "axisCustom": 2, "axisStandard": 35, "contextCount": 527, "dts": { "calculationLink": { "local": [ "nwn-20200630_cal.xml" ] }, "definitionLink": { "local": [ "nwn-20200630_def.xml" ], "remote": [ "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-eedm-def-2019-01-31.xml", "http://xbrl.fasb.org/srt/2019/elts/srt-eedm1-def-2019-01-31.xml" ] }, "inline": { "local": [ "a2020q2form10-qdocument.htm" ] }, "labelLink": { "local": [ "nwn-20200630_lab.xml" ], "remote": [ "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-doc-2019-01-31.xml", "https://xbrl.sec.gov/dei/2019/dei-doc-2019-01-31.xml" ] }, "presentationLink": { "local": [ "nwn-20200630_pre.xml" ] }, "referenceLink": { "remote": [ "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-ref-2019-01-31.xml", "https://xbrl.sec.gov/dei/2019/dei-ref-2019-01-31.xml" ] }, "schema": { "local": [ "nwn-20200630.xsd" ], "remote": [ "http://xbrl.fasb.org/srt/2019/elts/srt-types-2019-01-31.xsd", "http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd", "http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd", "http://www.xbrl.org/2003/xl-2003-12-31.xsd", "http://www.xbrl.org/2003/xlink-2003-12-31.xsd", "http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd", "http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd", "http://www.xbrl.org/2006/ref-2006-02-27.xsd", "http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd", "http://www.xbrl.org/2005/xbrldt-2005.xsd", "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd", "http://xbrl.fasb.org/us-gaap/2019/elts/us-roles-2019-01-31.xsd", "http://xbrl.fasb.org/srt/2019/elts/srt-roles-2019-01-31.xsd", "https://xbrl.sec.gov/country/2017/country-2017-01-31.xsd", "http://xbrl.fasb.org/us-gaap/2019/elts/us-types-2019-01-31.xsd", "http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd", "http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd", "http://www.xbrl.org/lrr/role/net-2009-12-16.xsd", "https://xbrl.sec.gov/currency/2019/currency-2019-01-31.xsd", "https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd", "https://xbrl.sec.gov/exch/2019/exch-2019-01-31.xsd", "http://xbrl.sec.gov/naics/2017/naics-2017-01-31.xsd", "http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd", "https://xbrl.sec.gov/stpr/2018/stpr-2018-01-31.xsd", "http://www.xbrl.org/lrr/role/reference-2009-12-16.xsd", "http://xbrl.fasb.org/us-gaap/2019/elts/us-parts-codification-2019-01-31.xsd", "http://www.xbrl.org/lrr/role/deprecated-2009-12-16.xsd" ] } }, "elementCount": 684, "entityCount": 1, "hidden": { "http://fasb.org/us-gaap/2019-01-31": 35, "http://www.nwnatural.com/20200630": 5, "http://xbrl.sec.gov/dei/2019-01-31": 12, "total": 52 }, "keyCustom": 72, "keyStandard": 410, "memberCustom": 56, "memberStandard": 38, "nsprefix": "nwn", "nsuri": "http://www.nwnatural.com/20200630", "report": { "R1": { "firstAnchor": { "ancestors": [ "span", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "dei:DocumentType", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "document", "isDefault": "true", "longName": "0001000 - Document - Document and Entity Information", "role": "http://www.nwnatural.com/role/DocumentAndEntityInformation", "shortName": "Document and Entity Information", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "span", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "dei:DocumentType", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R10": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EarningsPerShareTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2102100 - Disclosure - Earnings Per Share", "role": "http://www.nwnatural.com/role/EarningsPerShare", "shortName": "Earnings Per Share", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EarningsPerShareTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R11": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SegmentReportingDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2103100 - Disclosure - Segment Information", "role": "http://www.nwnatural.com/role/SegmentInformation", "shortName": "Segment Information", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SegmentReportingDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R12": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RevenueFromContractWithCustomerTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2105100 - Disclosure - Revenue (Notes)", "role": "http://www.nwnatural.com/role/RevenueNotes", "shortName": "Revenue (Notes)", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RevenueFromContractWithCustomerTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R13": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LeasesOfLesseeDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2106100 - Disclosure - Leases (Notes)", "role": "http://www.nwnatural.com/role/LeasesNotes", "shortName": "Leases (Notes)", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LeasesOfLesseeDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R14": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2108100 - Disclosure - Stock-Based Compensation", "role": "http://www.nwnatural.com/role/StockBasedCompensation", "shortName": "Stock-Based Compensation", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R15": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2109100 - Disclosure - Debt", "role": "http://www.nwnatural.com/role/Debt", "shortName": "Debt", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R16": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2110100 - Disclosure - Pension and Other Postretirement Benefit Costs", "role": "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCosts", "shortName": "Pension and Other Postretirement Benefit Costs", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R17": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:IncomeTaxDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2111100 - Disclosure - Income Tax", "role": "http://www.nwnatural.com/role/IncomeTax", "shortName": "Income Tax", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:IncomeTaxDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R18": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2112100 - Disclosure - Property, Plant and Equipment (Notes)", "role": "http://www.nwnatural.com/role/PropertyPlantAndEquipmentNotes", "shortName": "Property, Plant and Equipment (Notes)", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R19": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "nwn:GasReservesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2113100 - Disclosure - Gas Reserves", "role": "http://www.nwnatural.com/role/GasReserves", "shortName": "Gas Reserves", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "nwn:GasReservesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R2": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:DisaggregationOfRevenueTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Revenues", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "1001000 - Statement - Consolidated Statements of Comprehensive Income", "role": "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "shortName": "Consolidated Statements of Comprehensive Income", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "lang": null, "name": "us-gaap:OperatingCostsAndExpenses", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R20": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:InvestmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2114100 - Disclosure - Investments", "role": "http://www.nwnatural.com/role/Investments", "shortName": "Investments", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:InvestmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R21": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BusinessCombinationDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2115100 - Disclosure - Business Combinations Business Combinations", "role": "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinations", "shortName": "Business Combinations Business Combinations", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BusinessCombinationDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R22": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2117100 - Disclosure - Derivative Instruments", "role": "http://www.nwnatural.com/role/DerivativeInstruments", "shortName": "Derivative Instruments", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R23": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EnvironmentalLossContingencyDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2118100 - Disclosure - Environmental Matters", "role": "http://www.nwnatural.com/role/EnvironmentalMatters", "shortName": "Environmental Matters", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EnvironmentalLossContingencyDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R24": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2119100 - Disclosure - Discontinued Operations", "role": "http://www.nwnatural.com/role/DiscontinuedOperations", "shortName": "Discontinued Operations", "subGroupType": "", "uniqueAnchor": null }, "R25": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PublicUtilitiesPolicyTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2201201 - Disclosure - Significant Accounting Policies (Policies)", "role": "http://www.nwnatural.com/role/SignificantAccountingPoliciesPolicies", "shortName": "Significant Accounting Policies (Policies)", "subGroupType": "policies", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PublicUtilitiesPolicyTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R26": { "firstAnchor": { "ancestors": [ "ix:continuation", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2301302 - Disclosure - Significant Accounting Policies (Tables)", "role": "http://www.nwnatural.com/role/SignificantAccountingPoliciesTables", "shortName": "Significant Accounting Policies (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R27": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2302301 - Disclosure - Earnings Per Share (Tables)", "role": "http://www.nwnatural.com/role/EarningsPerShareTables", "shortName": "Earnings Per Share (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R28": { "firstAnchor": { "ancestors": [ "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2303301 - Disclosure - Segment Information (Tables)", "role": "http://www.nwnatural.com/role/SegmentInformationTables", "shortName": "Segment Information (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R29": { "firstAnchor": { "ancestors": [ "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisaggregationOfRevenueTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2305301 - Disclosure - Revenue (Tables)", "role": "http://www.nwnatural.com/role/RevenueTables", "shortName": "Revenue (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisaggregationOfRevenueTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R3": { "firstAnchor": null, "groupType": "statement", "isDefault": "false", "longName": "1001501 - Statement - Consolidated Statements of Comprehensive Income (Parentheticals)", "role": "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals", "shortName": "Consolidated Statements of Comprehensive Income (Parentheticals)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R30": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OperatingLeaseLeaseIncomeTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2306301 - Disclosure - Leases (Tables)", "role": "http://www.nwnatural.com/role/LeasesTables", "shortName": "Leases (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OperatingLeaseLeaseIncomeTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R31": { "firstAnchor": { "ancestors": [ "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2309301 - Disclosure - Debt (Tables)", "role": "http://www.nwnatural.com/role/DebtTables", "shortName": "Debt (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R32": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfNetBenefitCostsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2310301 - Disclosure - Pension and Other Postretirement Benefit Costs (Tables)", "role": "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsTables", "shortName": "Pension and Other Postretirement Benefit Costs (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfNetBenefitCostsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R33": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2311301 - Disclosure - Income Tax (Tables)", "role": "http://www.nwnatural.com/role/IncomeTaxTables", "shortName": "Income Tax (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R34": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfPublicUtilityPropertyPlantAndEquipmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2312301 - Disclosure - Property, Plant and Equipment (Tables)", "role": "http://www.nwnatural.com/role/PropertyPlantAndEquipmentTables", "shortName": "Property, Plant and Equipment (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfPublicUtilityPropertyPlantAndEquipmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R35": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "nwn:GasReservesTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2313301 - Disclosure - Gas Reserves (Tables)", "role": "http://www.nwnatural.com/role/GasReservesTables", "shortName": "Gas Reserves (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "nwn:GasReservesTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R36": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2315301 - Disclosure - Business Combinations Business Combinations (Tables)", "role": "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsTables", "shortName": "Business Combinations Business Combinations (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R37": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2317301 - Disclosure - Derivative Instruments (Tables)", "role": "http://www.nwnatural.com/role/DerivativeInstrumentsTables", "shortName": "Derivative Instruments (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R38": { "firstAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2318301 - Disclosure - Environmental Matters (Tables)", "role": "http://www.nwnatural.com/role/EnvironmentalMattersTables", "shortName": "Environmental Matters (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R39": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2319301 - Disclosure - Discontinued Operations (Tables)", "role": "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "shortName": "Discontinued Operations (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_us-gaap_IncomeStatementLocationAxis_nwn_NorthwestHoldingsMember", "decimals": null, "lang": "en-US", "name": "us-gaap:ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R4": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "1002000 - Statement - Consolidated Balance Sheets", "role": "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "shortName": "Consolidated Balance Sheets", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "lang": null, "name": "us-gaap:AccountsReceivableGrossCurrent", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R40": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RegulatoryAssetsCurrent", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2401403 - Disclosure - Significant Accounting Policies - Regulatory Asset Disclosure (Details)", "role": "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "shortName": "Significant Accounting Policies - Regulatory Asset Disclosure (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfRegulatoryAssetsTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_us-gaap_RegulatoryAssetAxis_us-gaap_OtherRegulatoryAssetsLiabilitiesMember", "decimals": "-3", "lang": null, "name": "us-gaap:RegulatoryAssetsNoncurrent", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R41": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RegulatoryLiabilityCurrent", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2401404 - Disclosure - Significant Accounting Policies - Regulatory Liability Disclosure (Details)", "role": "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails", "shortName": "Significant Accounting Policies - Regulatory Liability Disclosure (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "-5", "lang": null, "name": "nwn:COVID19IncrementalCosts", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R42": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock", "ix:continuation", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:AllowanceForDoubtfulAccountsReceivable", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2401405 - Disclosure - Significant Accounting Policies - Credit Losses - ASU 2016-13 (Details)", "role": "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details", "shortName": "Significant Accounting Policies - Credit Losses - ASU 2016-13 (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock", "ix:continuation", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:AllowanceForDoubtfulAccountsReceivable", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R43": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:IncomeLossFromContinuingOperations", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2402402 - Disclosure - Earnings Per Share (Details)", "role": "http://www.nwnatural.com/role/EarningsPerShareDetails", "shortName": "Earnings Per Share (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "lang": null, "name": "us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements", "reportCount": 1, "unique": true, "unitRef": "shares", "xsiNil": "false" } }, "R44": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_srt_ConsolidationItemsAxis_us-gaap_OperatingSegmentsMember", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:NumberOfReportableSegments", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2403402 - Disclosure - Segment Information - Narrative (Details)", "role": "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "shortName": "Segment Information - Narrative (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_srt_ConsolidationItemsAxis_us-gaap_OperatingSegmentsMember", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:NumberOfReportableSegments", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" } }, "R45": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:DisaggregationOfRevenueTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Revenues", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2403403 - Disclosure - Segment Information - Schedule of Summarized Financial Information by Segment (Details)", "role": "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails", "shortName": "Segment Information - Schedule of Summarized Financial Information by Segment (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD_srt_ConsolidationItemsAxis_us-gaap_OperatingSegmentsMember_us-gaap_StatementBusinessSegmentsAxis_nwn_NaturalGasDistributionMember", "decimals": "-3", "lang": null, "name": "us-gaap:DepreciationAndAmortization", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R46": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:DisaggregationOfRevenueTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Revenues", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2403404 - Disclosure - Segment Information - Additional Segment Information (Details)", "role": "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "shortName": "Segment Information - Additional Segment Information (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "nwn:NGDMarginTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD_srt_ConsolidationItemsAxis_us-gaap_OperatingSegmentsMember_us-gaap_StatementBusinessSegmentsAxis_nwn_NaturalGasDistributionMember", "decimals": "-3", "lang": null, "name": "us-gaap:RegulatedOperatingRevenue", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R47": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:DisaggregationOfRevenueTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2405402 - Disclosure - Revenue - Disaggregation of Revenue (Details)", "role": "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "shortName": "Revenue - Disaggregation of Revenue (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:DisaggregationOfRevenueTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R48": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LessorSalesTypeLeaseTermOfContract1", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2405403 - Disclosure - Revenue - Revenue, Remaining Performance Obligation (Details)", "role": "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails", "shortName": "Revenue - Revenue, Remaining Performance Obligation (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis.domain_2020-07-01", "decimals": "-5", "lang": null, "name": "us-gaap:RevenueRemainingPerformanceObligation", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R49": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LessorSalesTypeLeaseRenewalTerm1", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2406402 - Disclosure - Leases - Lease Revenue (Details)", "role": "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "shortName": "Leases - Lease Revenue (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:OperatingLeaseLeaseIncomeTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "lang": null, "name": "us-gaap:SalesTypeLeaseLeaseIncome", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R5": { "firstAnchor": null, "groupType": "statement", "isDefault": "false", "longName": "1002501 - Statement - Consolidated Balance Sheets (Parentheticals)", "role": "http://www.nwnatural.com/role/ConsolidatedBalanceSheetsParentheticals", "shortName": "Consolidated Balance Sheets (Parentheticals)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R50": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:ResidualValueOfLeasedAsset", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2406403 - Disclosure - Leases - Lease Expense (Details)", "role": "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "shortName": "Leases - Lease Expense (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:LeaseCostTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "lang": null, "name": "us-gaap:OperatingLeaseExpense", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R51": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2406404 - Disclosure - Leases - Lease Asset and Liabilities (Details)", "role": "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "shortName": "Leases - Lease Asset and Liabilities (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "nwn:OperatingLeaseWeightedAverageRemainingTermandDiscountRatesTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2019Q4", "decimals": null, "lang": "en-US", "name": "us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R52": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_us-gaap_AwardTypeAxis_us-gaap_PerformanceSharesMember_us-gaap_PlanNameAxis_nwn_LongTermIncentivePlanMember", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted", "reportCount": 1, "unique": true, "unitRef": "shares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2408401 - Disclosure - Stock-Based Compensation (Details)", "role": "http://www.nwnatural.com/role/StockBasedCompensationDetails", "shortName": "Stock-Based Compensation (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_us-gaap_AwardTypeAxis_us-gaap_PerformanceSharesMember_us-gaap_PlanNameAxis_nwn_LongTermIncentivePlanMember", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted", "reportCount": 1, "unique": true, "unitRef": "shares", "xsiNil": "false" } }, "R53": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ShortTermBorrowings", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2409402 - Disclosure - Debt Short-term Debt (Details)", "role": "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "shortName": "Debt Short-term Debt (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "lang": "en-US", "name": "nwn:CommercialpaperMaximumremainingmaturity", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R54": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LongTermDebt", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2409403 - Disclosure - Long-Term Debt (Details)", "role": "http://www.nwnatural.com/role/LongTermDebtDetails", "shortName": "Long-Term Debt (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD_dei_LegalEntityAxis_nwn_NorthwestNaturalGasCompanyMember_us-gaap_DebtInstrumentAxis_nwn_Note3.60SeriesDue2050Member", "decimals": "-5", "lang": null, "name": "us-gaap:ProceedsFromIssuanceOfDebt", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R55": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DebtInstrumentCarryingAmount", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2409404 - Disclosure - Debt Fair Value of Long Term Debt (Details)", "role": "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "shortName": "Debt Fair Value of Long Term Debt (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "ix:continuation", "us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DebtInstrumentCarryingAmount", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R56": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfNetBenefitCostsTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD_us-gaap_RetirementPlanTypeAxis_us-gaap_PensionPlansDefinedBenefitMember", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DefinedBenefitPlanServiceCost", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2410402 - Disclosure - Pension and Other Postretirement Benefit Costs - Net Periodic Benefit Cost (Details)", "role": "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails", "shortName": "Pension and Other Postretirement Benefit Costs - Net Periodic Benefit Cost (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfNetBenefitCostsTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD_us-gaap_RetirementPlanTypeAxis_us-gaap_PensionPlansDefinedBenefitMember", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DefinedBenefitPlanServiceCost", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R57": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q1", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2410403 - Disclosure - Pension and Other Postretirement Benefit Costs - Amounts Recognized in Accumulated Other Comprehensive Loss (Details)", "role": "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails", "shortName": "Pension and Other Postretirement Benefit Costs - Amounts Recognized in Accumulated Other Comprehensive Loss (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q1", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R58": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:PensionAndOtherPostretirementBenefitContributions", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2410404 - Disclosure - Pension and Other Postretirement Benefit Costs - Narrative (Details)", "role": "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNarrativeDetails", "shortName": "Pension and Other Postretirement Benefit Costs - Narrative (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:PensionAndOtherPostretirementBenefitContributions", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R59": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2411402 - Disclosure - Income Tax (Details)", "role": "http://www.nwnatural.com/role/IncomeTaxDetails", "shortName": "Income Tax (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2QTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R6": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2018Q4", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "1003000 - Statement - Consolidated Statement of Shareholders' Equity", "role": "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "shortName": "Consolidated Statement of Shareholders' Equity", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2018Q4", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R60": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2019Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:PropertyPlantAndEquipmentGross", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2412402 - Disclosure - Property, Plant and Equipment (Details)", "role": "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "shortName": "Property, Plant and Equipment (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfPublicUtilityPropertyPlantAndEquipmentTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2019Q2_us-gaap_StatementBusinessSegmentsAxis_nwn_NaturalGasDistributionMember", "decimals": "-3", "lang": null, "name": "us-gaap:PropertyPlantAndEquipmentGross", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R61": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-6", "first": true, "lang": null, "name": "nwn:TotalCumulativeGasReservesInvestment", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2413402 - Disclosure - Gas Reserves (Details)", "role": "http://www.nwnatural.com/role/GasReservesDetails", "shortName": "Gas Reserves (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-6", "first": true, "lang": null, "name": "nwn:TotalCumulativeGasReservesInvestment", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R62": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "nwn:GasReservesTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DeferredGasCost", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2413403 - Disclosure - Gas Reserves - Investment (Details)", "role": "http://www.nwnatural.com/role/GasReservesInvestmentDetails", "shortName": "Gas Reserves - Investment (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "nwn:GasReservesTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "lang": null, "name": "nwn:GasReservesNoncurrentGross", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R63": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:EquityMethodInvestmentUnderlyingEquityInNetAssets", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2414401 - Disclosure - Investments (Details)", "role": "http://www.nwnatural.com/role/InvestmentsDetails", "shortName": "Investments (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:EquityMethodInvestmentUnderlyingEquityInNetAssets", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R64": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Goodwill", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2415402 - Disclosure - Business Combinations Business Combinations (Details)", "role": "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails", "shortName": "Business Combinations Business Combinations (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "0", "lang": null, "name": "us-gaap:GoodwillImpairmentLoss", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R65": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_dei_LegalEntityAxis_nwn_NorthwestNaturalGasCompanyMember_nwn_GasYearAxis_nwn_GasYear20192020Member_us-gaap_DerivativeInstrumentRiskAxis_nwn_FinancialMember", "decimals": "2", "first": true, "lang": null, "name": "nwn:TargetHedgeAchieved", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2417402 - Disclosure - Derivative Instruments Notional Amounts (Details)", "role": "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "shortName": "Derivative Instruments Notional Amounts (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_dei_LegalEntityAxis_nwn_NorthwestNaturalGasCompanyMember_nwn_GasYearAxis_nwn_GasYear20192020Member_us-gaap_DerivativeInstrumentRiskAxis_nwn_FinancialMember", "decimals": "2", "first": true, "lang": null, "name": "nwn:TargetHedgeAchieved", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" } }, "R66": { "firstAnchor": { "ancestors": [ "span", "span", "ix:continuation", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeFairValueOfDerivativeNet", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2417403 - Disclosure - Derivative Instruments Fair Value (Details)", "role": "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "shortName": "Derivative Instruments Fair Value (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "ix:continuation", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeFairValueOfDerivativeNet", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R67": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2019Q2YTD_us-gaap_DerivativeInstrumentRiskAxis_nwn_FinancialMember", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeGainOnDerivative", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2417404 - Disclosure - Unrealized and Realized Gain/Loss (Details)", "role": "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails", "shortName": "Unrealized and Realized Gain/Loss (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2019Q2YTD_us-gaap_DerivativeInstrumentRiskAxis_nwn_FinancialMember", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeGainOnDerivative", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R68": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:AdditionalCollateralAggregateFairValue", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2417405 - Disclosure - Derivative Instruments Credit Rating (Details)", "role": "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "shortName": "Derivative Instruments Credit Rating (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:AdditionalCollateralAggregateFairValue", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R69": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "nwn:EnvironmentalRegulatoryTableTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_srt_StatementGeographicalAxis_stpr_OR", "decimals": "4", "first": true, "lang": null, "name": "nwn:RemediationRecoveryPercentage", "reportCount": 1, "unitRef": "number", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2418402 - Disclosure - Environmental Matters (Details)", "role": "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "shortName": "Environmental Matters (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2_srt_StatementGeographicalAxis_stpr_WA", "decimals": "4", "lang": null, "name": "nwn:RemediationRecoveryPercentage", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" } }, "R7": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:NetIncomeLoss", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "1004000 - Statement - Consolidated Statement of Cash Flows", "role": "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "shortName": "Consolidated Statement of Cash Flows", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": "-3", "lang": null, "name": "us-gaap:DepreciationDepletionAndAmortization", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R70": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:AccruedEnvironmentalLossContingenciesCurrent", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2418403 - Disclosure - Environmental Matters - Environmental Sites (Details)", "role": "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "shortName": "Environmental Matters - Environmental Sites (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2019Q4", "decimals": "-3", "lang": null, "name": "us-gaap:AccruedEnvironmentalLossContingenciesCurrent", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R71": { "firstAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RegulatoryAssetsCurrent", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2418404 - Disclosure - Environmental Matters - Regulatory Deferred Assets (Details)", "role": "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "shortName": "Environmental Matters - Regulatory Deferred Assets (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "nwn:EnvironmentalRegulatoryTableTableTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "4", "lang": null, "name": "nwn:RemediationNonrecoveryPercentage", "reportCount": 1, "unique": true, "unitRef": "number", "xsiNil": "false" } }, "R72": { "firstAnchor": { "ancestors": [ "span", "span", "div", "ix:continuation", "td", "tr", "table", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2020Q2", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperation", "reportCount": 1, "unitRef": "usd", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2419402 - Disclosure - Discontinued Operations (Details)", "role": "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "shortName": "Discontinued Operations (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "span", "div", "td", "tr", "table", "div", "div", "us-gaap:ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock", "ix:continuation", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FI2019Q4_us-gaap_DisposalGroupClassificationAxis_us-gaap_DiscontinuedOperationsHeldForSaleOrDisposedOfBySaleMember_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_nwn_GillRanchMember", "decimals": "-3", "lang": null, "name": "us-gaap:DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet", "reportCount": 1, "unique": true, "unitRef": "usd", "xsiNil": "false" } }, "R8": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2101100 - Disclosure - Organization and Principles of Consolidation", "role": "http://www.nwnatural.com/role/OrganizationAndPrinciplesOfConsolidation", "shortName": "Organization and Principles of Consolidation", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R9": { "firstAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SignificantAccountingPoliciesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "2101100 - Disclosure - Significant Accounting Policies", "role": "http://www.nwnatural.com/role/SignificantAccountingPolicies", "shortName": "Significant Accounting Policies", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "div", "div", "body", "html" ], "baseRef": "a2020q2form10-qdocument.htm", "contextRef": "FD2020Q2YTD", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SignificantAccountingPoliciesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } } }, "segmentCount": 106, "tag": { "dei_AmendmentFlag": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.", "label": "Amendment Flag", "terseLabel": "Amendment Flag" } } }, "localname": "AmendmentFlag", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_CityAreaCode": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Area code of city", "label": "City Area Code", "terseLabel": "City Area Code" } } }, "localname": "CityAreaCode", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_CurrentFiscalYearEndDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "End date of current fiscal year in the format --MM-DD.", "label": "Current Fiscal Year End Date", "terseLabel": "Current Fiscal Year End Date" } } }, "localname": "CurrentFiscalYearEndDate", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "gMonthDayItemType" }, "dei_DocumentFiscalPeriodFocus": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fiscal period values are FY, Q1, Q2, and Q3. 1st, 2nd and 3rd quarter 10-Q or 10-QT statements have value Q1, Q2, and Q3 respectively, with 10-K, 10-KT or other fiscal year statements having FY.", "label": "Document Fiscal Period Focus", "terseLabel": "Document Fiscal Period Focus" } } }, "localname": "DocumentFiscalPeriodFocus", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "fiscalPeriodItemType" }, "dei_DocumentFiscalYearFocus": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.", "label": "Document Fiscal Year Focus", "terseLabel": "Document Fiscal Year Focus" } } }, "localname": "DocumentFiscalYearFocus", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "gYearItemType" }, "dei_DocumentInformationLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Document Information [Line Items]", "terseLabel": "Document Information [Line Items]" } } }, "localname": "DocumentInformationLineItems", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "stringItemType" }, "dei_DocumentInformationTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Container to support the formal attachment of each official or unofficial, public or private document as part of a submission package.", "label": "Document Information [Table]", "terseLabel": "Document Information [Table]" } } }, "localname": "DocumentInformationTable", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "stringItemType" }, "dei_DocumentPeriodEndDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.", "label": "Document Period End Date", "terseLabel": "Document Period End Date" } } }, "localname": "DocumentPeriodEndDate", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "dateItemType" }, "dei_DocumentQuarterlyReport": { "auth_ref": [ "r444" ], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true only for a form used as an quarterly report.", "label": "Document Quarterly Report", "terseLabel": "Document Quarterly Report" } } }, "localname": "DocumentQuarterlyReport", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_DocumentTransitionReport": { "auth_ref": [ "r445" ], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true only for a form used as a transition report.", "label": "Document Transition Report", "terseLabel": "Document Transition Report" } } }, "localname": "DocumentTransitionReport", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_DocumentType": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.", "label": "Document Type", "terseLabel": "Document Type" } } }, "localname": "DocumentType", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "submissionTypeItemType" }, "dei_EntityAddressAddressLine1": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Address Line 1 such as Attn, Building Name, Street Name", "label": "Entity Address, Address Line One", "terseLabel": "Entity Address, Address Line One" } } }, "localname": "EntityAddressAddressLine1", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressCityOrTown": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of the City or Town", "label": "Entity Address, City or Town", "terseLabel": "Entity Address, City or Town" } } }, "localname": "EntityAddressCityOrTown", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressPostalZipCode": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Code for the postal or zip code", "label": "Entity Address, Postal Zip Code", "terseLabel": "Entity Address, Postal Zip Code" } } }, "localname": "EntityAddressPostalZipCode", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressStateOrProvince": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of the state or province.", "label": "Entity Address, State or Province", "terseLabel": "Entity Address, State or Province" } } }, "localname": "EntityAddressStateOrProvince", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "stateOrProvinceItemType" }, "dei_EntityCentralIndexKey": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.", "label": "Entity Central Index Key", "terseLabel": "Entity Central Index Key" } } }, "localname": "EntityCentralIndexKey", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "centralIndexKeyItemType" }, "dei_EntityCommonStockSharesOutstanding": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.", "label": "Entity Common Stock, Shares Outstanding", "terseLabel": "Entity Common Stock, Shares Outstanding" } } }, "localname": "EntityCommonStockSharesOutstanding", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "sharesItemType" }, "dei_EntityCurrentReportingStatus": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indicate 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure.", "label": "Entity Current Reporting Status", "terseLabel": "Entity Current Reporting Status" } } }, "localname": "EntityCurrentReportingStatus", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "yesNoItemType" }, "dei_EntityDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "All the names of the entities being reported upon in a document. Any legal structure used to conduct activities or to hold assets. Some examples of such structures are corporations, partnerships, limited liability companies, grantor trusts, and other trusts. This item does not include business and geographical segments which are included in the geographical or business segments domains.", "label": "Entity [Domain]", "terseLabel": "Entity [Domain]" } } }, "localname": "EntityDomain", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals", "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/DocumentAndEntityInformation", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/IncomeTaxDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "dei_EntityEmergingGrowthCompany": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "Indicate if registrant meets the emerging growth company criteria.", "label": "Entity Emerging Growth Company", "terseLabel": "Entity Emerging Growth Company" } } }, "localname": "EntityEmergingGrowthCompany", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntityFileNumber": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.", "label": "Entity File Number", "terseLabel": "Entity File Number" } } }, "localname": "EntityFileNumber", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "fileNumberItemType" }, "dei_EntityFilerCategory": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "Indicate whether the registrant is one of the following: Large Accelerated Filer, Accelerated Filer, Non-accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure.", "label": "Entity Filer Category", "terseLabel": "Entity Filer Category" } } }, "localname": "EntityFilerCategory", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "filerCategoryItemType" }, "dei_EntityIncorporationStateCountryCode": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two-character EDGAR code representing the state or country of incorporation.", "label": "Entity Incorporation, State or Country Code", "terseLabel": "Entity Incorporation, State or Country Code" } } }, "localname": "EntityIncorporationStateCountryCode", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "edgarStateCountryItemType" }, "dei_EntityInteractiveDataCurrent": { "auth_ref": [ "r447" ], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true when the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).", "label": "Entity Interactive Data Current", "terseLabel": "Entity Interactive Data Current" } } }, "localname": "EntityInteractiveDataCurrent", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "yesNoItemType" }, "dei_EntityRegistrantName": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.", "label": "Entity Registrant Name", "terseLabel": "Entity Registrant Name" } } }, "localname": "EntityRegistrantName", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityShellCompany": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true when the registrant is a shell company as defined in Rule 12b-2 of the Exchange Act.", "label": "Entity Shell Company", "terseLabel": "Entity Shell Company" } } }, "localname": "EntityShellCompany", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntitySmallBusiness": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "Indicates that the company is a Smaller Reporting Company (SRC).", "label": "Entity Small Business", "terseLabel": "Entity Small Business" } } }, "localname": "EntitySmallBusiness", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntityTaxIdentificationNumber": { "auth_ref": [ "r446" ], "lang": { "en-US": { "role": { "documentation": "The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.", "label": "Entity Tax Identification Number", "terseLabel": "Entity Tax Identification Number" } } }, "localname": "EntityTaxIdentificationNumber", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "employerIdItemType" }, "dei_LegalEntityAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The set of legal entities associated with a report.", "label": "Legal Entity [Axis]", "terseLabel": "Legal Entity [Axis]" } } }, "localname": "LegalEntityAxis", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals", "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/DocumentAndEntityInformation", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/IncomeTaxDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "dei_LocalPhoneNumber": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Local phone number for entity.", "label": "Local Phone Number", "terseLabel": "Local Phone Number" } } }, "localname": "LocalPhoneNumber", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_Security12bTitle": { "auth_ref": [ "r442" ], "lang": { "en-US": { "role": { "documentation": "Title of a 12(b) registered security.", "label": "Title of 12(b) Security", "terseLabel": "Title of 12(b) Security" } } }, "localname": "Security12bTitle", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "securityTitleItemType" }, "dei_SecurityExchangeName": { "auth_ref": [ "r443" ], "lang": { "en-US": { "role": { "documentation": "Name of the Exchange on which a security is registered.", "label": "Security Exchange Name", "terseLabel": "Security Exchange Name" } } }, "localname": "SecurityExchangeName", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "edgarExchangeCodeItemType" }, "dei_TradingSymbol": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Trading symbol of an instrument as listed on an exchange.", "label": "Trading Symbol", "terseLabel": "Trading Symbol" } } }, "localname": "TradingSymbol", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DocumentAndEntityInformation" ], "xbrltype": "tradingSymbolItemType" }, "nwn_A2019AwardMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A 2019 Award [Member]", "label": "A 2019 Award [Member]", "terseLabel": "A 2019 Award [Member]" } } }, "localname": "A2019AwardMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "nwn_A2019Awardand2020AwardMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A 2019 Award and 2020 Award [Member]", "label": "A 2019 Award and 2020 Award [Member]", "terseLabel": "A 2019 Award and 2020 Award [Member]" } } }, "localname": "A2019Awardand2020AwardMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "nwn_A2020AwardMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A 2020 Award [Member]", "label": "A 2020 Award [Member]", "terseLabel": "A 2020 Award [Member]" } } }, "localname": "A2020AwardMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "nwn_A364DayTermLoanDue2021Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "364-Day Term Loan, Due 2021 [Member]", "label": "364-Day Term Loan, Due 2021 [Member]", "terseLabel": "364-Day Term Loan, Due 2021 [Member]" } } }, "localname": "A364DayTermLoanDue2021Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "domainItemType" }, "nwn_AccruedunbilledandotherMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Accrued unbilled and other [Member]", "label": "Accrued unbilled and other [Member]", "terseLabel": "Accrued unbilled and other [Member]" } } }, "localname": "AccruedunbilledandotherMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "domainItemType" }, "nwn_AdditionalRatePerTherm": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Additional rate per therm", "label": "Additional Rate Per Therm", "terseLabel": "Additional rate per therm" } } }, "localname": "AdditionalRatePerTherm", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_AlternativerevenueMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Alternative revenue [Member]", "label": "Alternative revenue [Member]", "terseLabel": "Alternative revenue [Member]" } } }, "localname": "AlternativerevenueMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_AmortizationofRegulatoryBalancingAccount": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 3.0, "parentTag": "nwn_DefinedBenefitPlanNetAmountChargedToExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amortization of Regulatory Balancing Account", "label": "Amortization of Regulatory Balancing Account", "terseLabel": "Amortization of Regulatory Balancing Account" } } }, "localname": "AmortizationofRegulatoryBalancingAccount", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "nwn_AnnualInsuranceProceedstoApplyAgainstRemediationCosts": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Annual Insurance Proceeds to Apply Against Remediation Costs", "label": "Annual Insurance Proceeds to Apply Against Remediation Costs", "terseLabel": "Annual insurance proceeds to apply against remediation costs" } } }, "localname": "AnnualInsuranceProceedstoApplyAgainstRemediationCosts", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_AnnualTariffRiderCollection": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Annual Tariff rider collection", "label": "Annual Tariff Rider Collection", "terseLabel": "Annual tariff rider collection" } } }, "localname": "AnnualTariffRiderCollection", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_ApplianceCenterRevenueMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Appliance Center Revenue [Member]", "label": "Appliance Center Revenue [Member]", "terseLabel": "Appliance Center Revenue [Member]" } } }, "localname": "ApplianceCenterRevenueMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_AssetManagementRevenueNetofRegulatorySharingMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Asset Management Revenue, Net of Regulatory Sharing [Member]", "label": "Asset Management Revenue, Net of Regulatory Sharing [Member]", "terseLabel": "Asset Management Revenue, Net of Regulatory Sharing [Member]" } } }, "localname": "AssetManagementRevenueNetofRegulatorySharingMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_BusinessAcquisitionConnectionsofAcquiredBusiness": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Business Acquisition, Connections of Acquired Business", "label": "Business Acquisition, Connections of Acquired Business", "terseLabel": "Business Acquisition, Connections of Acquired Business" } } }, "localname": "BusinessAcquisitionConnectionsofAcquiredBusiness", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "stringItemType" }, "nwn_COVID19IncrementalCosts": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "COVID-19 Incremental Costs", "label": "COVID-19 Incremental Costs", "terseLabel": "COVID-19 Incremental Costs" } } }, "localname": "COVID19IncrementalCosts", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "monetaryItemType" }, "nwn_CentralServiceCenterMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to the Central Service Center environmental site", "label": "Central Service Center [Member]", "terseLabel": "Central Service Center [Member]" } } }, "localname": "CentralServiceCenterMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_CollateralPostedwithNWNaturalCounterpartiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Collateral Posted with NW Natural Counterparties", "label": "Collateral Posted with NW Natural Counterparties [Member]", "terseLabel": "Collateral Posted with NW Natural Counterparties [Member]" } } }, "localname": "CollateralPostedwithNWNaturalCounterpartiesMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "domainItemType" }, "nwn_CommercialMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commercial [Member]", "label": "Commercial [Member]", "terseLabel": "Commercial [Member]" } } }, "localname": "CommercialMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "domainItemType" }, "nwn_CommercialpaperAverageremainingmaturity": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commercial paper, Average remaining maturity", "label": "Commercial paper, Average remaining maturity", "terseLabel": "Commercial paper, Average remaining maturity" } } }, "localname": "CommercialpaperAverageremainingmaturity", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "durationItemType" }, "nwn_CommercialpaperMaximumremainingmaturity": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commercial paper, Maximum remaining maturity", "label": "Commercial paper, Maximum remaining maturity", "terseLabel": "Commercial paper, Maximum remaining maturity" } } }, "localname": "CommercialpaperMaximumremainingmaturity", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "durationItemType" }, "nwn_CompressedNaturalGasLeaseMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Compressed Natural Gas Lease [Member]", "label": "Compressed Natural Gas Lease [Member]", "terseLabel": "Compressed Natural Gas Lease [Member]" } } }, "localname": "CompressedNaturalGasLeaseMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_CostIncurredStudiesandDesignCosts": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Cost Incurred, Studies and Design Costs", "label": "Cost Incurred, Studies and Design Costs", "terseLabel": "Additional studies and design costs" } } }, "localname": "CostIncurredStudiesandDesignCosts", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_CreditLossesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit Losses [Abstract]", "label": "Credit Losses [Abstract]" } } }, "localname": "CreditLossesAbstract", "nsuri": "http://www.nwnatural.com/20200630", "xbrltype": "stringItemType" }, "nwn_DebtInstrumentCovenantConsolidatedIndebtednesstoCapitalizationRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio", "label": "Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio", "terseLabel": "Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio" } } }, "localname": "DebtInstrumentCovenantConsolidatedIndebtednesstoCapitalizationRatio", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "percentItemType" }, "nwn_DecouplingMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Decoupling [Member]", "label": "Decoupling [Member]", "terseLabel": "Decoupling [Member]" } } }, "localname": "DecouplingMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "nwn_DeferredTaxesRelatedToGasReserves": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": 2.0, "parentTag": "nwn_NetGasReservesInvestment", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Deferred taxes related to gas reserves", "label": "Deferred Taxes Related To Gas Reserves", "terseLabel": "Less: Deferred taxes on gas reserves" } } }, "localname": "DeferredTaxesRelatedToGasReserves", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DefinedBenefitPlanAmountAllocatedToConstruction": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 2.0, "parentTag": "nwn_DefinedBenefitPlanNetPeriodicBenefitCostChargedToExpense", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Net periodic benefit cost allocated to construction.", "label": "Defined Benefit Plan Amount Allocated To Construction", "negatedTerseLabel": "Amount allocated to construction" } } }, "localname": "DefinedBenefitPlanAmountAllocatedToConstruction", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DefinedBenefitPlanNetAmountChargedToExpense": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Net periodic benefit cost charged to expense.", "label": "Defined Benefit Plan Net Amount Charged To Expense", "totalLabel": "Net amount charged to expense" } } }, "localname": "DefinedBenefitPlanNetAmountChargedToExpense", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DefinedBenefitPlanNetPeriodicBenefitCostChargedToExpense": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 1.0, "parentTag": "nwn_DefinedBenefitPlanNetAmountChargedToExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Defined Benefit Plan Net Periodic Benefit Cost Charged To Expense", "label": "Defined Benefit Plan Net Periodic Benefit Cost Charged To Expense", "totalLabel": "Defined Benefit Plan Net Periodic Benefit Cost Charged To Expense" } } }, "localname": "DefinedBenefitPlanNetPeriodicBenefitCostChargedToExpense", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DiscontinuedOperationAccumulatedDepreciationonPropertyPlantandEquipmentNonCurrent": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 5.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Discontinued Operation, Accumulated Depreciation on Property, Plant and Equipment, Non-Current", "label": "Discontinued Operation, Accumulated Depreciation on Property, Plant and Equipment, Non-Current", "terseLabel": "Less: Accumulated depreciation" } } }, "localname": "DiscontinuedOperationAccumulatedDepreciationonPropertyPlantandEquipmentNonCurrent", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DiscontinuedOperationOperatingLeaseLiabilities": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 3.0, "parentTag": "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Discontinued Operation, Operating Lease Liabilities", "label": "Discontinued Operation, Operating Lease Liabilities", "terseLabel": "Operating lease liabilities" } } }, "localname": "DiscontinuedOperationOperatingLeaseLiabilities", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DiscontinuedOperationOperatingleaseRightofUseAsset": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 6.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Discontinued Operation, Operating lease, Right-of-Use Asset", "label": "Discontinued Operation, Operating lease, Right-of-Use Asset", "terseLabel": "Operating lease right of use asset" } } }, "localname": "DiscontinuedOperationOperatingleaseRightofUseAsset", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_DocumentAndEntityInformationAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "General document and entity information", "label": "Document and Entity Information [Abstract]" } } }, "localname": "DocumentAndEntityInformationAbstract", "nsuri": "http://www.nwnatural.com/20200630", "xbrltype": "stringItemType" }, "nwn_EncanaOilGasUSAInc.Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Encana Oil & Gas (USA) Inc. [Member]", "label": "Encana Oil & Gas (USA) Inc. [Member]", "terseLabel": "Encana Oil & Gas (USA) Inc." } } }, "localname": "EncanaOilGasUSAInc.Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails" ], "xbrltype": "domainItemType" }, "nwn_EnvironmentalActivityAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The name of the environmental sites itemized in a table of environmental activities.", "label": "Environmental Activity [Axis]", "terseLabel": "Environmental Activity [Axis]" } } }, "localname": "EnvironmentalActivityAxis", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "stringItemType" }, "nwn_EnvironmentalActivityDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The name of the environmental sites itemized in a table of environmental activities.", "label": "Environmental Activity [Domain]", "terseLabel": "Environmental Activity [Domain]" } } }, "localname": "EnvironmentalActivityDomain", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "domainItemType" }, "nwn_EnvironmentalEarningsTestReserve": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Environmental Earnings Test Reserve", "label": "Environmental Earnings Test Reserve", "terseLabel": "Environmental Earnings Test Reserve" } } }, "localname": "EnvironmentalEarningsTestReserve", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_EnvironmentalRegulatoryInsuranceProceedsandInterest": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails": { "order": 3.0, "parentTag": "us-gaap_RegulatoryAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Environmental Regulatory Insurance Proceeds and Interest", "label": "Environmental Regulatory Insurance Proceeds and Interest", "terseLabel": "Insurance proceeds and interest" } } }, "localname": "EnvironmentalRegulatoryInsuranceProceedsandInterest", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_EnvironmentalRegulatoryTableTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Environmental Regulatory Table [Table Text Block]", "label": "Environmental Regulatory Table [Table Text Block]", "terseLabel": "Environmental Regulatory Table" } } }, "localname": "EnvironmentalRegulatoryTableTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersTables" ], "xbrltype": "textBlockItemType" }, "nwn_Environmentalmonitoringactivitiesduration": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Environmental monitoring activities, duration", "label": "Environmental monitoring activities, duration", "terseLabel": "Environmental monitoring activities, duration" } } }, "localname": "Environmentalmonitoringactivitiesduration", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "durationItemType" }, "nwn_ExciseTaxes": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 7.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of excise taxes collected by a public utility, which are deducted as a cost of sales.", "label": "Excise Taxes", "terseLabel": "Revenue taxes" } } }, "localname": "ExciseTaxes", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "nwn_FinanceLeasesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Finance Leases [Abstract]", "label": "Finance Leases [Abstract]", "terseLabel": "Finance Leases [Abstract]" } } }, "localname": "FinanceLeasesAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "nwn_FinancialMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Financial [Member]", "label": "Financial [Member]", "terseLabel": "Financial [Member]" } } }, "localname": "FinancialMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "nwn_FrontStreetMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to the Front Street environmental site", "label": "Front Street [Member]", "terseLabel": "Front Street [Member]" } } }, "localname": "FrontStreetMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "domainItemType" }, "nwn_GasReservesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "", "label": "Gas Reserves [Abstract]" } } }, "localname": "GasReservesAbstract", "nsuri": "http://www.nwnatural.com/20200630", "xbrltype": "stringItemType" }, "nwn_GasReservesAmortization": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": 3.0, "parentTag": "nwn_TotalGasReserves", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Cumulative regulatory amortization of gas reserves investment.", "label": "Gas Reserves Amortization", "terseLabel": "Less: Accumulated amortization" } } }, "localname": "GasReservesAmortization", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_GasReservesDisclosureTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gas Reserves Disclosure [Text Block]", "label": "Gas Reserves Disclosure [Text Block]", "terseLabel": "Gas Reserves" } } }, "localname": "GasReservesDisclosureTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReserves" ], "xbrltype": "textBlockItemType" }, "nwn_GasReservesInvestment": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Gas reserves investment", "label": "Gas Reserves Investment", "terseLabel": "Gas reserves investment" } } }, "localname": "GasReservesInvestment", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_GasReservesNoncurrentGross": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": 2.0, "parentTag": "nwn_TotalGasReserves", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Gross carrying amount as of the balance sheet date of investments in Gas Reserves expected to be recovered in longer than one year.", "label": "Gas Reserves Noncurrent Gross", "terseLabel": "Gas reserves, non-current" } } }, "localname": "GasReservesNoncurrentGross", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_GasReservesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of information pertaining to gas reserves.", "label": "Gas Reserves Table [Text Block]", "terseLabel": "Gas Reserves" } } }, "localname": "GasReservesTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesTables" ], "xbrltype": "textBlockItemType" }, "nwn_GasStorageRevenueNetofRegulatorySharingMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gas Storage Revenue, Net of Regulatory Sharing [Member]", "label": "Gas Storage Revenue, Net of Regulatory Sharing [Member]", "terseLabel": "Gas Storage Revenue, Net of Regulatory Sharing [Member]" } } }, "localname": "GasStorageRevenueNetofRegulatorySharingMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_GasYear20182019Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gas Year 2018 - 2019 [Member]", "label": "Gas Year 2018 - 2019 [Member]", "terseLabel": "Gas Year 2018 - 2019 [Member]" } } }, "localname": "GasYear20182019Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "nwn_GasYear20192020Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gas Year 2019 - 2020 [Member]", "label": "Gas Year 2019 - 2020 [Member]", "terseLabel": "Gas Year 2019 - 2020 [Member]" } } }, "localname": "GasYear20192020Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "nwn_GasYearAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gas Year [Axis]", "label": "Gas Year [Axis]", "terseLabel": "Gas Year [Axis]" } } }, "localname": "GasYearAxis", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "stringItemType" }, "nwn_GasYearDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "[Domain] for Gas Year [Axis]", "label": "Gas Year [Domain]", "terseLabel": "Gas Year [Domain]" } } }, "localname": "GasYearDomain", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "nwn_GascoSiltronicSedimentsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to the Gasco Siltronic Sediments environmental site", "label": "Gasco Siltronic Sediments [Member]", "terseLabel": "Gasco/Siltronic Sediments" } } }, "localname": "GascoSiltronicSedimentsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_GascoSiltronicUplandMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to the Gasco environmental site", "label": "Gasco/Siltronic Upland [Member]", "terseLabel": "Gasco/Siltronic Upland [Member]" } } }, "localname": "GascoSiltronicUplandMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_GascoUplandsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gasco Uplands [Member]", "label": "Gasco Uplands [Member]", "terseLabel": "Gasco Uplands [Member]" } } }, "localname": "GascoUplandsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_GillRanchMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gill Ranch [Member]", "label": "Gill Ranch [Member]", "terseLabel": "Gill Ranch [Member]" } } }, "localname": "GillRanchMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "domainItemType" }, "nwn_HedgeRateTerm": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Hedge Rate, Term", "label": "Hedge Rate, Term", "terseLabel": "Term of hedge rate" } } }, "localname": "HedgeRateTerm", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails" ], "xbrltype": "durationItemType" }, "nwn_IndustrialMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Industrial [Member]", "label": "Industrial [Member]", "terseLabel": "Industrial [Member]" } } }, "localname": "IndustrialMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "domainItemType" }, "nwn_JonahEnergyLLCMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Jonah Energy LLC [Member]", "label": "Jonah Energy LLC [Member]", "terseLabel": "Jonah Energy LLC" } } }, "localname": "JonahEnergyLLCMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "domainItemType" }, "nwn_LeaseExpenseAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Lease Expense [Abstract]", "label": "Lease Expense [Abstract]", "terseLabel": "Lease Expense [Abstract]" } } }, "localname": "LeaseExpenseAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "stringItemType" }, "nwn_LeaseNotYetCommencedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Lease Not Yet Commenced [Abstract]", "label": "Lease Not Yet Commenced [Abstract]", "terseLabel": "Commencement of Significant Lease [Abstract]" } } }, "localname": "LeaseNotYetCommencedAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "nwn_LeasePaymentstobeReceived": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received", "label": "Lease Payments to be Received", "totalLabel": "Total lease revenue" } } }, "localname": "LeasePaymentstobeReceived", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedFiveYears": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 5.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Five Years", "label": "Lease Payments to be Received, Five Years", "terseLabel": "Lease Payments to be Received, Five Years" } } }, "localname": "LeasePaymentstobeReceivedFiveYears", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedFourYears": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 4.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Four Years", "label": "Lease Payments to be Received, Four Years", "terseLabel": "Lease Payments to be Received, Four Years" } } }, "localname": "LeasePaymentstobeReceivedFourYears", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedRemainderofFiscalYear": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 1.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Remainder of Fiscal Year", "label": "Lease Payments to be Received, Remainder of Fiscal Year", "terseLabel": "Lease Payments to be Received, Remainder of Fiscal Year" } } }, "localname": "LeasePaymentstobeReceivedRemainderofFiscalYear", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedThereafter": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 6.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Thereafter", "label": "Lease Payments to be Received, Thereafter", "terseLabel": "Lease Payments to be Received, Thereafter" } } }, "localname": "LeasePaymentstobeReceivedThereafter", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedThreeYears": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 3.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Three Years", "label": "Lease Payments to be Received, Three Years", "terseLabel": "Lease Payments to be Received, Three Years" } } }, "localname": "LeasePaymentstobeReceivedThreeYears", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeasePaymentstobeReceivedTwoYears": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 2.0, "parentTag": "nwn_LeasePaymentstobeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Lease Payments to be Received, Two Years", "label": "Lease Payments to be Received, Two Years", "terseLabel": "Lease Payments to be Received, Two Years" } } }, "localname": "LeasePaymentstobeReceivedTwoYears", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "nwn_LeaseRevenueAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Lease Revenue [Abstract]", "label": "Lease Revenue [Abstract]", "terseLabel": "Lease Revenue [Abstract]" } } }, "localname": "LeaseRevenueAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "nwn_LeasesCashFlowAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Leases Cash Flow [Abstract]", "label": "Leases Cash Flow [Abstract]", "terseLabel": "Leases Cash Flow [Abstract]" } } }, "localname": "LeasesCashFlowAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "nwn_LeasingrevenueMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Leasing revenue [Member]", "label": "Leasing revenue [Member]", "terseLabel": "Leasing revenue [Member]" } } }, "localname": "LeasingrevenueMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_LesseeLeasesSupplementalCashFlowInformationTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Lessee, Leases, Supplemental Cash Flow Information [Table Text Block]", "label": "Lessee, Leases, Supplemental Cash Flow Information [Table Text Block]", "terseLabel": "Lessee, Leases, Supplemental Cash Flow Information" } } }, "localname": "LesseeLeasesSupplementalCashFlowInformationTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "nwn_LongTermIncentivePlanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Long Term Incentive Plan [Member]", "label": "Long Term Incentive Plan [Member]", "terseLabel": "Long Term Incentive Plan" } } }, "localname": "LongTermIncentivePlanMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "nwn_MaturityofOperatingLeaseLiabilitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Maturity of Operating Lease Liabilities [Abstract]", "label": "Maturity of Operating Lease Liabilities [Abstract]", "terseLabel": "Maturity of Operating Lease Liabilities [Abstract]" } } }, "localname": "MaturityofOperatingLeaseLiabilitiesAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "nwn_NGDMarginTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the components of the margin in the Utility segment.", "label": "NGD Margin [Table Text Block]", "terseLabel": "NGD Margin" } } }, "localname": "NGDMarginTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationTables" ], "xbrltype": "textBlockItemType" }, "nwn_NRDLiabilityClaimYakamaNation": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "NRD Liability Claim Yakama Nation", "label": "NRD Liability Claim Yakama Nation", "terseLabel": "NRD liability claim yakama nation" } } }, "localname": "NRDLiabilityClaimYakamaNation", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_NaturalGasDistributionMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Natural Gas Distribution [Member]", "label": "Natural Gas Distribution [Member]", "terseLabel": "Natural Gas Distribution [Member]" } } }, "localname": "NaturalGasDistributionMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "nwn_NaturalGasSalesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Natural Gas Sales [Member]", "label": "Natural Gas Sales [Member]", "terseLabel": "Natural Gas Sales [Member]" } } }, "localname": "NaturalGasSalesMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_NaturalGasThermsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Natural Gas Therms [Member]", "label": "Natural Gas Therms [Member]", "terseLabel": "Natural Gas Therms [Member]" } } }, "localname": "NaturalGasThermsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "nwn_NetGasReservesInvestment": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Gas reserves investment net of amortization and deferred taxes.", "label": "Net Gas Reserves Investment", "totalLabel": "Net investment in gas reserves" } } }, "localname": "NetGasReservesInvestment", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_NewHeadquartersLeaseMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "New Headquarters Lease [Member]", "label": "New Headquarters Lease [Member]", "terseLabel": "New Headquarters Lease [Member]" } } }, "localname": "NewHeadquartersLeaseMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_NewHeadquartersLeaseRenewalTerm1of2Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "New Headquarters Lease Renewal Term 1 of 2 [Member]", "label": "New Headquarters Lease Renewal Term 1 of 2 [Member]", "terseLabel": "New Headquarters Lease Renewal Term 1 of 2 [Member]" } } }, "localname": "NewHeadquartersLeaseRenewalTerm1of2Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "domainItemType" }, "nwn_NewHeadquartersLeaseRenewalTerm2of2Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "New Headquarters Lease Renewal Term 2 of 2 [Member]", "label": "New Headquarters Lease Renewal Term 2 of 2 [Member]", "terseLabel": "New Headquarters Lease Renewal Term 2 of 2 [Member]" } } }, "localname": "NewHeadquartersLeaseRenewalTerm2of2Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "domainItemType" }, "nwn_NorthMistLeaseMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "North Mist Lease [Member]", "label": "North Mist Lease [Member]", "terseLabel": "North Mist Lease [Member]" } } }, "localname": "NorthMistLeaseMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "domainItemType" }, "nwn_NorthwestHoldingsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Northwest Holdings [Member]", "label": "Northwest Holdings [Member]", "terseLabel": "Northwest Holdings [Member]" } } }, "localname": "NorthwestHoldingsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "nwn_NorthwestHoldingsandNorthwestNaturalMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Northwest Holdings and Northwest Natural [Member]", "label": "Northwest Holdings and Northwest Natural [Member]", "terseLabel": "Northwest Holdings and Northwest Natural [Member]" } } }, "localname": "NorthwestHoldingsandNorthwestNaturalMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "nwn_NorthwestNaturalGasCompanyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Northwest Natural Gas Company [Member]", "label": "Northwest Natural Gas Company [Member]", "terseLabel": "Northwest Natural Gas Company [Member]" } } }, "localname": "NorthwestNaturalGasCompanyMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals", "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/DocumentAndEntityInformation", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/IncomeTaxDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "nwn_Note3.60SeriesDue2050Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Note 360 Series Due 2050 [Member]", "label": "Note 3.60 Series Due 2050 [Member]", "terseLabel": "Note 3.60 Series Due 2050 [Member]" } } }, "localname": "Note3.60SeriesDue2050Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "domainItemType" }, "nwn_Note537SeriesDue2020Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Note 537 Series Due 2020 [Member]", "label": "Note 537 Series Due 2020 [Member]", "terseLabel": "Note 537 Series Due 2020 [Member]" } } }, "localname": "Note537SeriesDue2020Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "domainItemType" }, "nwn_NumberofAmendedComplaintsFiled": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of Amended Complaints Filed", "label": "Number of Amended Complaints Filed", "terseLabel": "Number of Amended Complaints Filed" } } }, "localname": "NumberofAmendedComplaintsFiled", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_OperatingLeaseAssetandLiabilitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating Lease Asset and Liabilities [Abstract]", "label": "Operating Lease Asset and Liabilities [Abstract]", "terseLabel": "Operating Lease Asset and Liabilities [Abstract]" } } }, "localname": "OperatingLeaseAssetandLiabilitiesAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "nwn_OperatingLeaseLeaseAssetandLiabilitiesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating Lease, Lease Asset and Liabilities [Table Text Block]", "label": "Operating Lease, Lease Asset and Liabilities [Table Text Block]", "terseLabel": "Operating Lease, Lease Asset and Liabilities" } } }, "localname": "OperatingLeaseLeaseAssetandLiabilitiesTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "nwn_OperatingLeaseTermsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating Lease Terms [Abstract]", "label": "Operating Lease Terms [Abstract]", "terseLabel": "Operating Lease Terms [Abstract]" } } }, "localname": "OperatingLeaseTermsAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "stringItemType" }, "nwn_OperatingLeaseWeightedAverageRemainingTermandDiscountRatesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating Lease, Weighted Average Remaining Term and Discount Rates [Table Text Block]", "label": "Operating Lease, Weighted Average Remaining Term and Discount Rates [Table Text Block]", "terseLabel": "Operating Lease, Weighted Average Remaining Term and Discount Rates [Table Text Block]" } } }, "localname": "OperatingLeaseWeightedAverageRemainingTermandDiscountRatesTableTextBlock", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "nwn_OperatingLeasesPaymenttobeReceivedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating Leases Payment to be Received [Abstract]", "label": "Operating Leases Payment to be Received [Abstract]", "terseLabel": "Operating Leases Payment to be Received [Abstract]" } } }, "localname": "OperatingLeasesPaymenttobeReceivedAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "nwn_OregonSteelMillsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to Oregon Steel Mills.", "label": "Oregon Steel Mills [Member]", "terseLabel": "Oregon Steel Mills [Member]" } } }, "localname": "OregonSteelMillsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_OtherNorthwestHoldingsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other Northwest Holdings [Member]", "label": "Other Northwest Holdings [Member]", "terseLabel": "Other Northwest Holdings [Member]" } } }, "localname": "OtherNorthwestHoldingsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "nwn_OtherNorthwestNaturalMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other Northwest Natural [Member]", "label": "Other Northwest Natural [Member]", "terseLabel": "Other Northwest Natural [Member]" } } }, "localname": "OtherNorthwestNaturalMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "nwn_OtherTaxExpenseBenefitdifferencestobeflowedthroughbyregulatorycommissions": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/IncomeTaxDetails": { "order": 3.0, "parentTag": "us-gaap_IncomeTaxExpenseBenefit", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Other Tax Expense (Benefit), differences to be flowed-through by regulatory commissions", "label": "Other Tax Expense (Benefit), differences to be flowed-through by regulatory commissions", "terseLabel": "Differences required to be flowed-through by regulatory commissions" } } }, "localname": "OtherTaxExpenseBenefitdifferencestobeflowedthroughbyregulatorycommissions", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "monetaryItemType" }, "nwn_OtherinsignificantacquisitionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other Insignificant acquisitions [Member]", "label": "Other insignificant acquisitions [Member]", "terseLabel": "Other insignificant acquisitions [Member]" } } }, "localname": "OtherinsignificantacquisitionsMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "domainItemType" }, "nwn_OtherrevenueMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other revenue [Member]", "label": "Other revenue [Member]", "terseLabel": "Other revenue [Member]" } } }, "localname": "OtherrevenueMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_PacificGasandElectricCompanyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Pacific Gas and Electric Company [Member]", "label": "Pacific Gas and Electric Company [Member]", "terseLabel": "Pacific Gas and Electric Company [Member]" } } }, "localname": "PacificGasandElectricCompanyMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "domainItemType" }, "nwn_PercentOfPreTaxIncomeFromGasStorageCreditedToDeferredRegulatoryAccount": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The percenage of pre-tax income from gas storage credited to a deferred regulatory account for crediting back to core utility customers when the costs of the capacity have not been included in utility rates.", "label": "Percent Of Pre Tax Income From Gas Storage Credited To Deferred Regulatory Account", "terseLabel": "Percent Of Pre Tax Income From Gas Storage Credited To Deferred Regulatory Account" } } }, "localname": "PercentOfPreTaxIncomeFromGasStorageCreditedToDeferredRegulatoryAccount", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "percentItemType" }, "nwn_PercentOfPreTaxIncomeFromGasStorageCreditedToDeferredRegulatoryAccountWhenInRates": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The percenage of pre-tax income from gas storage credited to a deferred regulatory account for crediting back to core utility customers when the costs of the capacity have been included in utility rates.", "label": "Percent Of Pre Tax Income From Gas Storage Credited To Deferred Regulatory Account When In Rates", "terseLabel": "Percent Of Pre Tax Income From Gas Storage Credited To Deferred Regulatory Account When In Rates" } } }, "localname": "PercentOfPreTaxIncomeFromGasStorageCreditedToDeferredRegulatoryAccountWhenInRates", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "percentItemType" }, "nwn_PercentOfPreTaxIncomeFromGasStorageRetainedWhenCostsOfCapacityAreInUtilityRates": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The percenage of pre-tax income from gas storage retained when the costs of the capacity have been included in utility rates.", "label": "Percent Of Pre Tax Income From Gas Storage Retained When The Costs Of The Capacity Are In Utility Rates", "terseLabel": "Percent Of Pre Tax Income From Gas Storage Retained When The Costs Of The Capacity Are In Utility Rates" } } }, "localname": "PercentOfPreTaxIncomeFromGasStorageRetainedWhenCostsOfCapacityAreInUtilityRates", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "percentItemType" }, "nwn_PercentOfPreTaxIncomeFromGasStorageRetainedWhenCostsOfCapacityAreNotInUtilityRates": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The percenage of pre-tax income from gas storage retained when the costs of the capacity have not been included in utility rates.", "label": "Percent Of Pre Tax Income From Gas Storage Retained When The Costs Of The Capacity Are Not In Utility Rates", "terseLabel": "Percent Of Pre Tax Income From Gas Storage Retained When The Costs Of The Capacity Are Not In Utility Rates" } } }, "localname": "PercentOfPreTaxIncomeFromGasStorageRetainedWhenCostsOfCapacityAreNotInUtilityRates", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "percentItemType" }, "nwn_PercentOwnershipInJointProject": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percent Ownership In Joint Project", "label": "Percent Ownership In Joint Project", "terseLabel": "Percent ownership" } } }, "localname": "PercentOwnershipInJointProject", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "percentItemType" }, "nwn_PhysicalMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Physical [Member]", "label": "Physical [Member]", "terseLabel": "Physical [Member]" } } }, "localname": "PhysicalMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "nwn_PortlandHarborMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Portland Harbor [Member]", "label": "Portland Harbor [Member]", "verboseLabel": "Portland Harbor [Member]" } } }, "localname": "PortlandHarborMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_PortlandHarborOtherMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discloses the details related to the Portland Harbor Other environmental site", "label": "Portland Harbor Other [Member]", "terseLabel": "Portland Harbor Other [Member]" } } }, "localname": "PortlandHarborOtherMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "nwn_PropertyPlantEquipmentnoncash": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Property, Plant, Equipment non-cash", "label": "Property, Plant, Equipment non-cash", "terseLabel": "Property, Plant, Equipment non-cash" } } }, "localname": "PropertyPlantEquipmentnoncash", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_ProposedRemediationPlanCleanUpCosts": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Proposed Remediation Plan, Clean-Up Costs", "label": "Proposed Remediation Plan, Clean-Up Costs", "terseLabel": "EPA final feasibility study and proposed remediation plan, clean-up costs, portland harbor" } } }, "localname": "ProposedRemediationPlanCleanUpCosts", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_ProposedRemediationPlanPercentageofCleanUpCosts": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Proposed Remediation Plan, Percentage of Clean-Up Costs", "label": "Proposed Remediation Plan, Percentage of Clean-Up Costs", "terseLabel": "Percentage of clean-up costs" } } }, "localname": "ProposedRemediationPlanPercentageofCleanUpCosts", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "percentItemType" }, "nwn_RegulatoryAssetsEnvironmentalRegulatoryAccruedSiteLiabilities": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails": { "order": 2.0, "parentTag": "us-gaap_RegulatoryAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Regulatory Assets, Environmental Regulatory Accrued Site Liabilities", "label": "Regulatory Assets, Environmental Regulatory Accrued Site Liabilities", "terseLabel": "Accrued site liabilities" } } }, "localname": "RegulatoryAssetsEnvironmentalRegulatoryAccruedSiteLiabilities", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_RegulatoryAssetsEnvironmentalRegulatoryDeferredCostandInterest": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails": { "order": 1.0, "parentTag": "us-gaap_RegulatoryAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Regulatory Assets, Environmental Regulatory Deferred Cost and Interest", "label": "Regulatory Assets, Environmental Regulatory Deferred Cost and Interest", "terseLabel": "Deferred costs and interest" } } }, "localname": "RegulatoryAssetsEnvironmentalRegulatoryDeferredCostandInterest", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_RegulatoryPensionDisallowance": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 2.0, "parentTag": "nwn_DefinedBenefitPlanNetAmountChargedToExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Regulatory Pension Disallowance", "label": "Regulatory Pension Disallowance", "terseLabel": "Regulatory Pension Disallowance" } } }, "localname": "RegulatoryPensionDisallowance", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "nwn_RemediationNonrecoveryPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Remediation Non-recovery Percentage", "label": "Remediation Non-recovery Percentage", "terseLabel": "Remediation Non-recovery Percentage" } } }, "localname": "RemediationNonrecoveryPercentage", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "percentItemType" }, "nwn_RemediationRecoveryPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Remediation Recovery Percentage", "label": "Remediation Recovery Percentage", "terseLabel": "Remediation Recovery Percentage" } } }, "localname": "RemediationRecoveryPercentage", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "percentItemType" }, "nwn_ResidentialMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Residential [Member]", "label": "Residential [Member]", "terseLabel": "Residential [Member]" } } }, "localname": "ResidentialMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "domainItemType" }, "nwn_SalestypeLeaseMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Sales-type Lease [Member]", "label": "Sales-type Lease [Member]", "terseLabel": "Sales-type Lease [Member]" } } }, "localname": "SalestypeLeaseMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "domainItemType" }, "nwn_SalestypeLeasesPaymentstobeReceivedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Sales-type Leases Payments to be Received [Abstract]", "label": "Sales-type Leases Payments to be Received [Abstract]", "terseLabel": "Sales-type Leases Payments to be Received [Abstract]" } } }, "localname": "SalestypeLeasesPaymentstobeReceivedAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "nwn_ShareBasedCompensationAwardTargetShare": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The target number of shares to be awarded under the plan if performance goals are achieved.", "label": "Share Based Compensation Award Target Share", "terseLabel": "Share Based Compensation Award Target Share" } } }, "localname": "ShareBasedCompensationAwardTargetShare", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "sharesItemType" }, "nwn_SharebasedCompensationArrangementsbySharebasedPaymentAwardConversionRatioPercentofTarget": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share-based Compensation Arrangements by Share-based Payment Award, Conversion Ratio, Percent of Target", "label": "Share-based Compensation Arrangements by Share-based Payment Award, Conversion Ratio, Percent of Target", "terseLabel": "Conversion ratio, percent of target" } } }, "localname": "SharebasedCompensationArrangementsbySharebasedPaymentAwardConversionRatioPercentofTarget", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "percentItemType" }, "nwn_SiteContingencyNumberofOtherThirdPartyDefendants": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Site Contingency, Number of Other Third-Party Defendants", "label": "Site Contingency, Number of Other Third-Party Defendants", "terseLabel": "Site Contingency, Number of Other Third-Party Defendants" } } }, "localname": "SiteContingencyNumberofOtherThirdPartyDefendants", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_SiteContingencyNumberofPotentiallyResponsibleParties": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Site Contingency, Number of Potentially Responsible Parties", "label": "Site Contingency, Number of Potentially Responsible Parties", "terseLabel": "Number of potentially responsible parties (more than)" } } }, "localname": "SiteContingencyNumberofPotentiallyResponsibleParties", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_SiteContingencyNumberofRemediationProjects": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Site Contingency, Number of Remediation Projects", "label": "Site Contingency, Number of Remediation Projects", "terseLabel": "Number of remediation projects" } } }, "localname": "SiteContingencyNumberofRemediationProjects", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_Sitecontingencynumberofmanagementpieces": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Site contingency: number of management pieces", "label": "Site contingency: number of management pieces", "terseLabel": "Site contingency: number of management pieces" } } }, "localname": "Sitecontingencynumberofmanagementpieces", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_StrandedDeferredTaxRemeasurementBenefit": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails": { "order": 2.0, "parentTag": "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Stranded Deferred Tax Remeasurement Benefit", "label": "Stranded Deferred Tax Remeasurement Benefit", "terseLabel": "Stranded Deferred Tax Remeasurement Benefit", "verboseLabel": "Reclassification of tax effects from the TCJA" } } }, "localname": "StrandedDeferredTaxRemeasurementBenefit", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "nwn_SuncadiaTWWaterMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Suncadia & T&W Water [Member]", "label": "Suncadia & T&W Water [Member]", "terseLabel": "Suncadia & T&W Water [Member]" } } }, "localname": "SuncadiaTWWaterMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "domainItemType" }, "nwn_SunriverMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Sunriver [Member]", "label": "Sunriver [Member]", "terseLabel": "Sunriver [Member]" } } }, "localname": "SunriverMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "domainItemType" }, "nwn_TargetAchievedMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Target Achieved [Member]", "label": "Target Achieved [Member]", "terseLabel": "Target Achieved [Member]" } } }, "localname": "TargetAchievedMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "nwn_TargetHedgeAchieved": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "TargetHedgeAchieved", "label": "TargetHedgeAchieved", "terseLabel": "TargetHedgeAchieved" } } }, "localname": "TargetHedgeAchieved", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "percentItemType" }, "nwn_TotalAnnualRemediationExpenseandInterest": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Total Annual Remediation Expense and Interest", "label": "Total Annual Remediation Expense and Interest", "terseLabel": "Total annual remediation expense and interest" } } }, "localname": "TotalAnnualRemediationExpenseandInterest", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_TotalCumulativeGasReservesInvestment": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total cumulative gas reserves investment", "label": "Total Cumulative Gas Reserves Investment", "terseLabel": "Total cumulative gas reserves investment" } } }, "localname": "TotalCumulativeGasReservesInvestment", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_TotalExpensesDiscontinuedOperations": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 2.0, "parentTag": "us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total Expenses Discontinued Operations", "label": "Total Expenses Discontinued Operations", "totalLabel": "Total expenses" } } }, "localname": "TotalExpensesDiscontinuedOperations", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "nwn_TotalGasReserves": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": 1.0, "parentTag": "nwn_NetGasReservesInvestment", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total gas reserves net of amortization.", "label": "Total Gas Reserves", "totalLabel": "Total gas reserves" } } }, "localname": "TotalGasReserves", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_TotalGasReservesInvestment": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total gas reserves investment", "label": "Total Gas Reserves Investment", "terseLabel": "Total Gas Reserves Investment" } } }, "localname": "TotalGasReservesInvestment", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "nwn_TotalLeasePaymentstobeReceivedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Total Lease Payments to be Received [Abstract]", "label": "Total Lease Payments to be Received [Abstract]", "terseLabel": "Total Lease Payments to be Received [Abstract]" } } }, "localname": "TotalLeasePaymentstobeReceivedAbstract", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "nwn_TransCanadaAmericanInvestmentsLtd.Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "TransCanada American Investments Ltd. [Member]", "label": "TransCanada American Investments Ltd. [Member]", "terseLabel": "TransCanada American Investments Ltd. [Member]" } } }, "localname": "TransCanadaAmericanInvestmentsLtd.Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "nwn_TrusteeCouncilMembersNumberofClaimants": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Trustee Council Members - Number of Claimants", "label": "Trustee Council Members - Number of Claimants", "terseLabel": "Trustee Council Members - Number of Claimants" } } }, "localname": "TrusteeCouncilMembersNumberofClaimants", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "integerItemType" }, "nwn_TwoyearTermLoanDue2021Member": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two-year Term Loan Due 2021 [Member]", "label": "Two-year Term Loan Due 2021 [Member]", "terseLabel": "Two-year Term Loan Due 2021 [Member]" } } }, "localname": "TwoyearTermLoanDue2021Member", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "domainItemType" }, "nwn_UndiscountedEnvironmentalRemediationExpense": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Undiscounted Environmental Remediation Expense", "label": "Undiscounted Environmental Remediation Expense", "terseLabel": "Undiscounted environmental remediation expense" } } }, "localname": "UndiscountedEnvironmentalRemediationExpense", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "nwn_UnrecognizedCompensationCostPeriodforRecognition": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The maximum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.", "label": "Unrecognized Compensation Cost, Period for Recognition", "terseLabel": "Unrecognized Compensation Cost, Period for Recognition" } } }, "localname": "UnrecognizedCompensationCostPeriodforRecognition", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "nwn_YakamaNationMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Yakama Nation [Member]", "label": "Yakama Nation [Member]", "verboseLabel": "Yakama Nation [Member]" } } }, "localname": "YakamaNationMember", "nsuri": "http://www.nwnatural.com/20200630", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "srt_ConsolidatedEntitiesAxis": { "auth_ref": [ "r431" ], "lang": { "en-US": { "role": { "label": "Consolidated Entities [Axis]", "terseLabel": "Consolidated Entities [Axis]" } } }, "localname": "ConsolidatedEntitiesAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "stringItemType" }, "srt_ConsolidatedEntitiesDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Consolidated Entities [Domain]", "terseLabel": "Consolidated Entities [Domain]" } } }, "localname": "ConsolidatedEntitiesDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "srt_ConsolidationItemsAxis": { "auth_ref": [ "r158", "r165" ], "lang": { "en-US": { "role": { "label": "Consolidation Items [Axis]", "terseLabel": "Consolidation Items [Axis]" } } }, "localname": "ConsolidationItemsAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "stringItemType" }, "srt_ConsolidationItemsDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Consolidation Items [Domain]", "terseLabel": "Consolidation Items [Domain]" } } }, "localname": "ConsolidationItemsDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "srt_LitigationCaseAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Litigation Case [Axis]", "terseLabel": "Litigation Case [Axis]" } } }, "localname": "LitigationCaseAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "stringItemType" }, "srt_LitigationCaseTypeDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Litigation Case [Domain]", "terseLabel": "Litigation Case [Domain]" } } }, "localname": "LitigationCaseTypeDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "domainItemType" }, "srt_MajorCustomersAxis": { "auth_ref": [ "r169", "r235", "r238", "r427" ], "lang": { "en-US": { "role": { "label": "Customer [Axis]", "terseLabel": "Customer [Axis]" } } }, "localname": "MajorCustomersAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "stringItemType" }, "srt_MaximumMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Maximum [Member]", "terseLabel": "Maximum [Member]" } } }, "localname": "MaximumMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "srt_MinimumMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Minimum [Member]", "terseLabel": "Minimum [Member]" } } }, "localname": "MinimumMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "srt_NameOfMajorCustomerDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Customer [Domain]", "terseLabel": "Customer [Domain]" } } }, "localname": "NameOfMajorCustomerDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "domainItemType" }, "srt_OwnershipAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Ownership [Axis]", "terseLabel": "Ownership [Axis]" } } }, "localname": "OwnershipAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "stringItemType" }, "srt_OwnershipDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Ownership [Domain]", "terseLabel": "Ownership [Domain]" } } }, "localname": "OwnershipDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "srt_ParentCompanyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Parent Company [Member]", "terseLabel": "Parent Company [Member]" } } }, "localname": "ParentCompanyMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "srt_ProductOrServiceAxis": { "auth_ref": [ "r167", "r235", "r236", "r424", "r425" ], "lang": { "en-US": { "role": { "label": "Product and Service [Axis]", "terseLabel": "Product and Service [Axis]" } } }, "localname": "ProductOrServiceAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "stringItemType" }, "srt_ProductsAndServicesDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Product and Service [Domain]", "terseLabel": "Product and Service [Domain]" } } }, "localname": "ProductsAndServicesDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "srt_ProvedDevelopedAndUndevelopedOilAndGasReserveQuantitiesTable": { "auth_ref": [ "r385", "r386", "r387", "r388", "r389", "r390", "r391" ], "lang": { "en-US": { "role": { "label": "Proved Developed and Undeveloped Oil and Gas Reserve Quantities [Table]", "terseLabel": "Proved Developed and Undeveloped Oil and Gas Reserve Quantities [Table]" } } }, "localname": "ProvedDevelopedAndUndevelopedOilAndGasReserveQuantitiesTable", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "stringItemType" }, "srt_RangeAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statistical Measurement [Axis]", "terseLabel": "Statistical Measurement [Axis]" } } }, "localname": "RangeAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "srt_RangeMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statistical Measurement [Domain]", "terseLabel": "Statistical Measurement [Domain]" } } }, "localname": "RangeMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LongTermDebtDetails", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "srt_ReserveQuantitiesLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Reserve Quantities [Line Items]", "terseLabel": "Reserve Quantities [Line Items]" } } }, "localname": "ReserveQuantitiesLineItems", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/GasReservesDetails", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "stringItemType" }, "srt_ScenarioForecastMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Forecast [Member]", "terseLabel": "Forecast [Member]" } } }, "localname": "ScenarioForecastMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "srt_ScenarioUnspecifiedDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Scenario [Domain]", "terseLabel": "Scenario [Domain]" } } }, "localname": "ScenarioUnspecifiedDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/InvestmentsDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "srt_SegmentGeographicalDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Geographical [Domain]", "terseLabel": "Geographical [Domain]" } } }, "localname": "SegmentGeographicalDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "domainItemType" }, "srt_StatementGeographicalAxis": { "auth_ref": [ "r168", "r235", "r237", "r426", "r429", "r430" ], "lang": { "en-US": { "role": { "label": "Geographical [Axis]", "terseLabel": "Geographical [Axis]" } } }, "localname": "StatementGeographicalAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "stringItemType" }, "srt_StatementScenarioAxis": { "auth_ref": [ "r219", "r384" ], "lang": { "en-US": { "role": { "label": "Scenario [Axis]", "terseLabel": "Scenario [Axis]", "verboseLabel": "Scenario [Axis]" } } }, "localname": "StatementScenarioAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/InvestmentsDetails", "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "stpr_OR": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "OREGON", "terseLabel": "Oregon [Member]" } } }, "localname": "OR", "nsuri": "http://xbrl.sec.gov/stpr/2018-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "domainItemType" }, "stpr_WA": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "WASHINGTON", "terseLabel": "WASHINGTON" } } }, "localname": "WA", "nsuri": "http://xbrl.sec.gov/stpr/2018-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails" ], "xbrltype": "domainItemType" }, "us-gaap_AccountingPoliciesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Accounting Policies [Abstract]" } } }, "localname": "AccountingPoliciesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_AccountingStandardsUpdate201802Member": { "auth_ref": [ "r96" ], "lang": { "en-US": { "role": { "documentation": "Accounting Standards Update 2018-02 Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.", "label": "Accounting Standards Update 2018-02 [Member]", "terseLabel": "Accounting Standards Update 2018-02 [Member]" } } }, "localname": "AccountingStandardsUpdate201802Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_AccountsPayableCurrent": { "auth_ref": [ "r65" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Accounts Payable, Current", "terseLabel": "Accounts payable" } } }, "localname": "AccountsPayableCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock": { "auth_ref": [ "r186" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of allowance for credit loss on accounts receivable.", "label": "Accounts Receivable, Allowance for Credit Loss [Table Text Block]", "terseLabel": "Accounts Receivable, Allowance for Credit Loss [Table Text Block]" } } }, "localname": "AccountsReceivableAllowanceForCreditLossTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_AccountsReceivableGrossCurrent": { "auth_ref": [ "r171", "r172" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.", "label": "Accounts Receivable, before Allowance for Credit Loss, Current", "terseLabel": "Accounts receivable" } } }, "localname": "AccountsReceivableGrossCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccountsReceivableNoncurrentCreditQualityIndicatorLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Accounts Receivable, Noncurrent, Credit Quality Indicator [Line Items]", "terseLabel": "Accounts Receivable, Noncurrent, Credit Quality Indicator [Line Items]" } } }, "localname": "AccountsReceivableNoncurrentCreditQualityIndicatorLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "stringItemType" }, "us-gaap_AccountsReceivableNoncurrentCreditQualityIndicatorTable": { "auth_ref": [ "r187" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about credit quality indicator for accounts receivable, classified as noncurrent.", "label": "Accounts Receivable, Noncurrent, Credit Quality Indicator [Table]", "terseLabel": "Accounts Receivable, Noncurrent, Credit Quality Indicator [Table]" } } }, "localname": "AccountsReceivableNoncurrentCreditQualityIndicatorTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "stringItemType" }, "us-gaap_AccruedEnvironmentalLossContingenciesCurrent": { "auth_ref": [ "r33", "r68", "r210", "r214", "r218" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.", "label": "Accrued Environmental Loss Contingencies, Current", "terseLabel": "Current Liabilities" } } }, "localname": "AccruedEnvironmentalLossContingenciesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent": { "auth_ref": [ "r72", "r210", "r214", "r218" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.", "label": "Accrued Environmental Loss Contingencies, Noncurrent", "terseLabel": "Non-Current Liabilities" } } }, "localname": "AccruedEnvironmentalLossContingenciesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccruedIncomeTaxesCurrent": { "auth_ref": [ "r48", "r396", "r410" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 4.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.", "label": "Accrued Income Taxes, Current", "terseLabel": "Taxes accrued" } } }, "localname": "AccruedIncomeTaxesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment": { "auth_ref": [ "r63", "r199" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_PropertyPlantAndEquipmentNet", "weight": -1.0 }, "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails": { "order": 3.0, "parentTag": "us-gaap_PropertyPlantAndEquipmentNet", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.", "label": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment", "terseLabel": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment", "verboseLabel": "Less: Accumulated depreciation" } } }, "localname": "AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax": { "auth_ref": [ "r84", "r86", "r87" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_StockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.", "label": "Accumulated Other Comprehensive Income (Loss), Net of Tax", "periodEndLabel": "Ending balance", "periodStartLabel": "Beginning balance", "terseLabel": "Accumulated other comprehensive loss" } } }, "localname": "AccumulatedOtherComprehensiveIncomeLossNetOfTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccumulatedOtherComprehensiveIncomeMember": { "auth_ref": [ "r83", "r87", "r90", "r314" ], "lang": { "en-US": { "role": { "documentation": "Accumulated increase (decrease) in equity from transactions and other events and circumstances from non-owner sources, attributable to the parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners.", "label": "AOCI Attributable to Parent [Member]", "terseLabel": "Accumulated Other Comprehensive Income (Loss) [Member]" } } }, "localname": "AccumulatedOtherComprehensiveIncomeMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_AdditionalCollateralAggregateFairValue": { "auth_ref": [ "r338" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.", "label": "Additional Collateral, Aggregate Fair Value", "terseLabel": "Additional Collateral, Aggregate Fair Value" } } }, "localname": "AdditionalCollateralAggregateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AdjustmentsForNewAccountingPronouncementsAxis": { "auth_ref": [ "r142" ], "lang": { "en-US": { "role": { "documentation": "Information by new accounting pronouncement.", "label": "Adjustments for New Accounting Pronouncements [Axis]", "terseLabel": "Adjustments for New Accounting Pronouncements [Axis]" } } }, "localname": "AdjustmentsForNewAccountingPronouncementsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "stringItemType" }, "us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts": { "auth_ref": [ "r226", "r231" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.", "label": "Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs", "negatedTerseLabel": "Stock issuance and costs" } } }, "localname": "AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]", "terseLabel": "Adjustments to reconcile net income to cash provided by operations:" } } }, "localname": "AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_AllocatedShareBasedCompensationExpense": { "auth_ref": [ "r271", "r280", "r284" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.", "label": "Share-based Payment Arrangement, Expense", "terseLabel": "Share-based Payment Arrangement, Expense" } } }, "localname": "AllocatedShareBasedCompensationExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AllowanceForDoubtfulAccountsReceivable": { "auth_ref": [ "r173", "r182", "r183", "r185" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of allowance for credit loss on accounts receivable.", "label": "Accounts Receivable, Allowance for Credit Loss", "terseLabel": "Accounts Receivable, Allowance for Credit Loss" } } }, "localname": "AllowanceForDoubtfulAccountsReceivable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "monetaryItemType" }, "us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent": { "auth_ref": [ "r57", "r173", "r182" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 4.0, "parentTag": "us-gaap_AssetsCurrent", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of allowance for credit loss on accounts receivable, classified as current.", "label": "Accounts Receivable, Allowance for Credit Loss, Current", "negatedLabel": "Allowance for uncollectible accounts" } } }, "localname": "AllowanceForDoubtfulAccountsReceivableCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease": { "auth_ref": [ "r186" ], "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in allowance for credit loss on accounts receivable.", "label": "Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)", "terseLabel": "Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)" } } }, "localname": "AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "monetaryItemType" }, "us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs": { "auth_ref": [ "r184" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of direct write-downs of accounts receivable charged against the allowance.", "label": "Accounts Receivable, Allowance for Credit Loss, Writeoff", "negatedTerseLabel": "Accounts Receivable, Allowance for Credit Loss, Writeoff" } } }, "localname": "AllowanceForDoubtfulAccountsReceivableWriteOffs", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "monetaryItemType" }, "us-gaap_AmortizationOfRegulatoryAsset": { "auth_ref": [ "r108", "r128" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 3.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The expense charged against earnings during the period to allocate the capitalized costs of regulatory assets over the periods expected to benefit from such costs.", "label": "Amortization of Regulatory Asset", "terseLabel": "Regulatory amortization of gas reserves" } } }, "localname": "AmortizationOfRegulatoryAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount": { "auth_ref": [ "r151" ], "lang": { "en-US": { "role": { "documentation": "Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.", "label": "Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount", "terseLabel": "Antidilutive shares" } } }, "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "sharesItemType" }, "us-gaap_ArrangementsAndNonarrangementTransactionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.", "label": "Collaborative Arrangement and Arrangement Other than Collaborative [Domain]", "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative [Domain]" } } }, "localname": "ArrangementsAndNonarrangementTransactionsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "domainItemType" }, "us-gaap_AssetRecoverableGasCostsMember": { "auth_ref": [ "r434" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of gas costs.", "label": "Asset Recoverable Gas Costs [Member]", "verboseLabel": "Gas costs [Member]" } } }, "localname": "AssetRecoverableGasCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_Assets": { "auth_ref": [ "r161", "r393", "r409" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.", "label": "Assets", "totalLabel": "Total assets", "verboseLabel": "Total assets" } } }, "localname": "Assets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AssetsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Assets [Abstract]", "terseLabel": "Assets:" } } }, "localname": "AssetsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_AssetsCurrent": { "auth_ref": [ "r30", "r31", "r78" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.", "label": "Assets, Current", "totalLabel": "Total current assets" } } }, "localname": "AssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AssetsCurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Assets, Current [Abstract]", "terseLabel": "Current assets:" } } }, "localname": "AssetsCurrentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_AssetsNoncurrent": { "auth_ref": [ "r36", "r37", "r38", "r39", "r40", "r41", "r42", "r43" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer.", "label": "Assets, Noncurrent", "totalLabel": "Total non-current assets" } } }, "localname": "AssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AssetsNoncurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Assets, Noncurrent [Abstract]", "terseLabel": "Non-current assets:" } } }, "localname": "AssetsNoncurrentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation": { "auth_ref": [ "r0", "r1", "r20", "r22", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as assets attributable to disposal group held for sale or disposed of.", "label": "Disposal Group, Including Discontinued Operation, Assets", "totalLabel": "Discontinued operations - total assets", "verboseLabel": "Discontinued operations - total assets" } } }, "localname": "AssetsOfDisposalGroupIncludingDiscontinuedOperation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent": { "auth_ref": [ "r0", "r1", "r20", "r22", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 11.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Assets, Current", "terseLabel": "Discontinued operations current assets" } } }, "localname": "AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AwardDateAxis": { "auth_ref": [ "r273", "r282" ], "lang": { "en-US": { "role": { "documentation": "Information by date or year award under share-based payment arrangement is granted.", "label": "Award Date [Axis]", "terseLabel": "Award Date [Axis]" } } }, "localname": "AwardDateAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_AwardDateDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Date or year award under share-based payment arrangement is granted.", "label": "Award Date [Domain]", "terseLabel": "Award Date [Domain]" } } }, "localname": "AwardDateDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_AwardTypeAxis": { "auth_ref": [ "r273", "r282" ], "lang": { "en-US": { "role": { "documentation": "Information by type of award under share-based payment arrangement.", "label": "Award Type [Axis]", "terseLabel": "Award Type [Axis]" } } }, "localname": "AwardTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_BalanceSheetLocationAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by location on balance sheet (statement of financial position).", "label": "Balance Sheet Location [Axis]", "terseLabel": "Balance Sheet Location [Axis]" } } }, "localname": "BalanceSheetLocationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_BalanceSheetLocationDomain": { "auth_ref": [ "r325", "r329" ], "lang": { "en-US": { "role": { "documentation": "Location in the balance sheet (statement of financial position).", "label": "Balance Sheet Location [Domain]", "terseLabel": "Balance Sheet Location [Domain]" } } }, "localname": "BalanceSheetLocationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_BusinessAcquisitionAcquireeDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Identification of the acquiree in a material business combination (or series of individually immaterial business combinations), which may include the name or other type of identification of the acquiree.", "label": "Business Acquisition, Acquiree [Domain]", "terseLabel": "Business Acquisition, Acquiree [Domain]" } } }, "localname": "BusinessAcquisitionAcquireeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_BusinessAcquisitionAxis": { "auth_ref": [ "r297", "r298" ], "lang": { "en-US": { "role": { "documentation": "Information by business combination or series of individually immaterial business combinations.", "label": "Business Acquisition [Axis]", "terseLabel": "Business Acquisition [Axis]" } } }, "localname": "BusinessAcquisitionAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessAcquisitionLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Business Acquisition [Line Items]", "terseLabel": "Business Acquisition [Line Items]" } } }, "localname": "BusinessAcquisitionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount": { "auth_ref": [ "r305" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.", "label": "Business Acquisition, Goodwill, Expected Tax Deductible Amount", "terseLabel": "Business Acquisition, Goodwill, Expected Tax Deductible Amount" } } }, "localname": "BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationConsiderationTransferred1": { "auth_ref": [ "r302", "r303", "r304" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.", "label": "Business Combination, Consideration Transferred", "terseLabel": "Business Combination, Consideration Transferred" } } }, "localname": "BusinessCombinationConsiderationTransferred1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationDisclosureTextBlock": { "auth_ref": [ "r306" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).", "label": "Business Combination Disclosure [Text Block]", "terseLabel": "Business Combination Disclosure" } } }, "localname": "BusinessCombinationDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinations" ], "xbrltype": "textBlockItemType" }, "us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual": { "auth_ref": [ "r296" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.", "label": "Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual", "terseLabel": "Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual" } } }, "localname": "BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets": { "auth_ref": [ "r300" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of assets acquired at the acquisition date.", "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets", "totalLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets": { "auth_ref": [ "r300" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": 1.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.", "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets", "terseLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]", "terseLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities": { "auth_ref": [ "r300" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": 5.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.", "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities", "negatedTerseLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets": { "auth_ref": [ "r286", "r300" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": 4.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets", "terseLabel": "Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill": { "auth_ref": [ "r300" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of intangible assets, excluding goodwill, acquired at the acquisition date.", "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill", "terseLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment": { "auth_ref": [ "r299", "r300" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": 2.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of property, plant, and equipment recognized as of the acquisition date.", "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment", "terseLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Business Combinations [Abstract]" } } }, "localname": "BusinessCombinationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_CapitalLeasesLessorBalanceSheetNetInvestmentInDirectFinancingAndSalesTypeLeasesNoncurrent": { "auth_ref": [ "r353" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 7.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The net amount due after one year of the balance sheet date or beyond the normal operating cycle, if longer, consisting of: (a) minimum lease payments due on direct financing and sales-type leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs on direct financing leases; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.", "label": "Capital Leases, Lessor Balance Sheet, Net Investment in Direct Financing and Sales Type Leases, Noncurrent", "terseLabel": "Assets under sales-type leases" } } }, "localname": "CapitalLeasesLessorBalanceSheetNetInvestmentInDirectFinancingAndSalesTypeLeasesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_CapitalizationLongtermDebtAndEquityAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Capitalization, Long-term Debt and Equity [Abstract]", "terseLabel": "Equity:" } } }, "localname": "CapitalizationLongtermDebtAndEquityAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_CashAndCashEquivalentsAtCarryingValue": { "auth_ref": [ "r29", "r59", "r130" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.", "label": "Cash and Cash Equivalents, at Carrying Value", "periodEndLabel": "Cash and cash equivalents, end of period", "periodStartLabel": "Cash and cash equivalents, beginning of period", "terseLabel": "Cash and cash equivalents" } } }, "localname": "CashAndCashEquivalentsAtCarryingValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_CashAndCashEquivalentsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.", "label": "Cash and Cash Equivalents [Member]", "terseLabel": "Cash and Cash Equivalents [Member]" } } }, "localname": "CashAndCashEquivalentsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect": { "auth_ref": [ "r123", "r349" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; excluding effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.", "label": "Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect", "totalLabel": "Increase in cash and cash equivalents" } } }, "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations": { "auth_ref": [ "r19", "r123" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 6.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.", "label": "Cash Provided by (Used in) Investing Activities, Discontinued Operations", "terseLabel": "Discontinued operations" } } }, "localname": "CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations": { "auth_ref": [ "r19", "r123" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 20.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.", "label": "Cash Provided by (Used in) Operating Activities, Discontinued Operations", "terseLabel": "Discontinued operations" } } }, "localname": "CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_CollateralAlreadyPostedAggregateFairValue": { "auth_ref": [ "r337" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.", "label": "Collateral Already Posted, Aggregate Fair Value", "terseLabel": "Additional Collateral, Aggregate Fair Value" } } }, "localname": "CollateralAlreadyPostedAggregateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_CommercialPaper": { "auth_ref": [ "r44", "r394", "r412" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.", "label": "Commercial Paper", "terseLabel": "Commercial Paper" } } }, "localname": "CommercialPaper", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_CommercialPaperMember": { "auth_ref": [ "r222" ], "lang": { "en-US": { "role": { "documentation": "Unsecured promissory note (generally negotiable) that provides institutions with short-term funds.", "label": "Commercial Paper [Member]", "terseLabel": "Commercial Paper [Member]" } } }, "localname": "CommercialPaperMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "domainItemType" }, "us-gaap_CommitmentsAndContingencies": { "auth_ref": [ "r73", "r218", "r400", "r416" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.", "label": "Commitments and Contingencies", "verboseLabel": "Commitments and contingencies (see Note 16 and Note 17)" } } }, "localname": "CommitmentsAndContingencies", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_CommodityContractMember": { "auth_ref": [ "r248", "r333" ], "lang": { "en-US": { "role": { "documentation": "Derivative instrument whose primary underlying risk is tied to commodity prices.", "label": "Commodity Contract [Member]", "terseLabel": "Natural gas commodity" } } }, "localname": "CommodityContractMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_CommonStockDividendsPerShareCashPaid": { "auth_ref": [ "r231" ], "lang": { "en-US": { "role": { "documentation": "Aggregate dividends paid during the period for each share of common stock outstanding.", "label": "Common Stock, Dividends, Per Share, Cash Paid", "terseLabel": "Dividends per share of common stock" } } }, "localname": "CommonStockDividendsPerShareCashPaid", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "perShareItemType" }, "us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Common stock held by shareholders with par value plus amounts in excess of par value or issuance value (in cases of no-par value stock).", "label": "Common Stock Including Additional Paid in Capital [Member]", "terseLabel": "Common Stock Including APIC [Member]" } } }, "localname": "CommonStockIncludingAdditionalPaidInCapitalMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_CommonStockNoParValue": { "auth_ref": [ "r52" ], "lang": { "en-US": { "role": { "documentation": "Face amount per share of no-par value common stock.", "label": "Common Stock, No Par Value", "terseLabel": "Par Value (in dollars per share)" } } }, "localname": "CommonStockNoParValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheetsParentheticals" ], "xbrltype": "perShareItemType" }, "us-gaap_CommonStockSharesAuthorized": { "auth_ref": [ "r52" ], "lang": { "en-US": { "role": { "documentation": "The maximum number of common shares permitted to be issued by an entity's charter and bylaws.", "label": "Common Stock, Shares Authorized", "terseLabel": "Shares Authorized (in shares)" } } }, "localname": "CommonStockSharesAuthorized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheetsParentheticals" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockSharesIssued": { "auth_ref": [ "r52" ], "lang": { "en-US": { "role": { "documentation": "Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.", "label": "Common Stock, Shares, Issued", "terseLabel": "Shares issued (in shares)" } } }, "localname": "CommonStockSharesIssued", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheetsParentheticals" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockSharesOutstanding": { "auth_ref": [ "r52", "r226" ], "lang": { "en-US": { "role": { "documentation": "Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.", "label": "Common Stock, Shares, Outstanding", "terseLabel": "Shares outstanding (in shares)" } } }, "localname": "CommonStockSharesOutstanding", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheetsParentheticals" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockValue": { "auth_ref": [ "r52" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_StockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.", "label": "Common Stock, Value, Issued", "verboseLabel": "Common stock" } } }, "localname": "CommonStockValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_ComprehensiveIncomeNetOfTax": { "auth_ref": [ "r92", "r94", "r95" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.", "label": "Comprehensive Income (Loss), Net of Tax, Attributable to Parent", "terseLabel": "Other comprehensive income", "totalLabel": "Comprehensive income (loss)" } } }, "localname": "ComprehensiveIncomeNetOfTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_CorporateNonSegmentMember": { "auth_ref": [ "r166" ], "lang": { "en-US": { "role": { "documentation": "Corporate headquarters or functional department that may not earn revenues or may earn revenues that are only incidental to the activities of the entity and is not considered an operating segment.", "label": "Corporate, Non-Segment [Member]", "terseLabel": "Corporate, Non-Segment [Member]" } } }, "localname": "CorporateNonSegmentMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "us-gaap_CostOfSalesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing cost of sales.", "label": "Cost of Sales [Member]", "terseLabel": "Benefit (expense) to cost of gas" } } }, "localname": "CostOfSalesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DebtDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Debt Disclosure [Abstract]" } } }, "localname": "DebtDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DebtDisclosureTextBlock": { "auth_ref": [ "r225" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.", "label": "Debt Disclosure [Text Block]", "terseLabel": "Debt" } } }, "localname": "DebtDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/Debt" ], "xbrltype": "textBlockItemType" }, "us-gaap_DebtInstrumentAxis": { "auth_ref": [ "r47", "r48", "r49", "r395", "r397", "r408" ], "lang": { "en-US": { "role": { "documentation": "Information by type of debt instrument, including, but not limited to, draws against credit facilities.", "label": "Debt Instrument [Axis]", "terseLabel": "Debt Instrument [Axis]" } } }, "localname": "DebtInstrumentAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentCarryingAmount": { "auth_ref": [ "r49", "r223", "r397", "r408" ], "calculation": { "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetailsCalc2": { "order": 1.0, "parentTag": "us-gaap_LongTermDebt", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.", "label": "Long-term Debt, Gross", "verboseLabel": "Gross long-term debt" } } }, "localname": "DebtInstrumentCarryingAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DebtInstrumentCovenantDescription": { "auth_ref": [ "r49", "r406" ], "lang": { "en-US": { "role": { "documentation": "Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.", "label": "Debt Instrument, Covenant Description", "terseLabel": "Debt Instrument, Covenant Description" } } }, "localname": "DebtInstrumentCovenantDescription", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentFairValue": { "auth_ref": [ "r348" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.", "label": "Debt Instrument, Fair Value Disclosure", "terseLabel": "Estimated fair value" } } }, "localname": "DebtInstrumentFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DebtInstrumentInterestRateStatedPercentage": { "auth_ref": [ "r70" ], "lang": { "en-US": { "role": { "documentation": "Contractual interest rate for funds borrowed, under the debt agreement.", "label": "Debt Instrument, Interest Rate, Stated Percentage", "terseLabel": "Stated interest rate" } } }, "localname": "DebtInstrumentInterestRateStatedPercentage", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "percentItemType" }, "us-gaap_DebtInstrumentLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Debt Instrument [Line Items]", "terseLabel": "Debt Instrument [Line Items]" } } }, "localname": "DebtInstrumentLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentNameDomain": { "auth_ref": [ "r71" ], "lang": { "en-US": { "role": { "documentation": "The name for the particular debt instrument or borrowing that distinguishes it from other debt instruments or borrowings, including draws against credit facilities.", "label": "Debt Instrument, Name [Domain]", "terseLabel": "Debt Instrument, Name [Domain]" } } }, "localname": "DebtInstrumentNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DebtInstrumentTable": { "auth_ref": [ "r71", "r136", "r227", "r228", "r229", "r230", "r350", "r351", "r352", "r407" ], "lang": { "en-US": { "role": { "documentation": "A table or schedule providing information pertaining to long-term debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer.", "label": "Schedule of Long-term Debt Instruments [Table]", "terseLabel": "Schedule of Long-term Debt Instruments [Table]" } } }, "localname": "DebtInstrumentTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DebtWeightedAverageInterestRate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Weighted average interest rate of debt outstanding.", "label": "Debt, Weighted Average Interest Rate", "terseLabel": "Debt, Weighted Average Interest Rate" } } }, "localname": "DebtWeightedAverageInterestRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "percentItemType" }, "us-gaap_DeferredCreditsAndOtherLiabilitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Deferred Credits and Other Liabilities [Abstract]", "terseLabel": "Deferred credits and other non-current liabilities:" } } }, "localname": "DeferredCreditsAndOtherLiabilitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income after one year or beyond the normal operating cycle, if longer and noncurrent obligations not separately disclosed in the balance sheet (other liabilities, noncurrent).", "label": "Deferred Credits and Other Liabilities, Noncurrent", "totalLabel": "Total deferred credits and other non-current liabilities" } } }, "localname": "DeferredCreditsAndOtherLiabilitiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredDerivativeGainLossMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of gain (loss) on derivative contracts.", "label": "Deferred Derivative Gain (Loss) [Member]", "terseLabel": "Deferred Derivative Gain (Loss) [Member]", "verboseLabel": "Deferred Derivative Gain (Loss) [Member]" } } }, "localname": "DeferredDerivativeGainLossMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DeferredGasCost": { "auth_ref": [ "r434" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 8.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/GasReservesInvestmentDetails": { "order": 1.0, "parentTag": "nwn_TotalGasReserves", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of capitalized gas costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer.", "label": "Deferred Gas Cost", "terseLabel": "Gas reserves" } } }, "localname": "DeferredGasCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/GasReservesInvestmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredIncomeTaxChargesMember": { "auth_ref": [ "r434", "r437", "r440", "r441" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of income taxes.", "label": "Deferred Income Tax Charge [Member]", "terseLabel": "Income taxes [Member]" } } }, "localname": "DeferredIncomeTaxChargesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DeferredIncomeTaxLiabilitiesNet": { "auth_ref": [ "r287", "r291" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.", "label": "Deferred Income Tax Liabilities, Net", "terseLabel": "Deferred tax liabilities" } } }, "localname": "DeferredIncomeTaxLiabilitiesNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredIncomeTaxesAndTaxCredits": { "auth_ref": [ "r129" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 4.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of deferred income tax expense (benefit) and income tax credits.", "label": "Deferred Income Taxes and Tax Credits", "terseLabel": "Deferred income taxes" } } }, "localname": "DeferredIncomeTaxesAndTaxCredits", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses": { "auth_ref": [ "r253", "r264", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 5.0, "parentTag": "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.", "label": "Defined Benefit Plan, Amortization of Gain (Loss)", "negatedTerseLabel": "Defined Benefit Plan, Amortization of Gain (Loss)" } } }, "localname": "DefinedBenefitPlanAmortizationOfGainsLosses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit": { "auth_ref": [ "r254", "r265", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 4.0, "parentTag": "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.", "label": "Defined Benefit Plan, Amortization of Prior Service Cost (Credit)", "terseLabel": "Amortization of net actuarial loss" } } }, "localname": "DefinedBenefitPlanAmortizationOfPriorServiceCostCredit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]", "terseLabel": "Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]" } } }, "localname": "DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear": { "auth_ref": [ "r266" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.", "label": "Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year", "terseLabel": "Estimated future employer contributions in next fiscal year" } } }, "localname": "DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNarrativeDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets": { "auth_ref": [ "r252", "r263", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 3.0, "parentTag": "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.", "label": "Defined Benefit Plan, Expected Return (Loss) on Plan Assets", "negatedTerseLabel": "Expected return on plan assets" } } }, "localname": "DefinedBenefitPlanExpectedReturnOnPlanAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanInterestCost": { "auth_ref": [ "r246", "r251", "r262", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 2.0, "parentTag": "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost recognized for passage of time related to defined benefit plan.", "label": "Defined Benefit Plan, Interest Cost", "terseLabel": "Interest cost" } } }, "localname": "DefinedBenefitPlanInterestCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost": { "auth_ref": [ "r249", "r260", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 1.0, "parentTag": "nwn_DefinedBenefitPlanNetPeriodicBenefitCostChargedToExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of net periodic benefit cost (credit) for defined benefit plan.", "label": "Defined Benefit Plan, Net Periodic Benefit Cost (Credit)", "totalLabel": "Net periodic benefit cost" } } }, "localname": "DefinedBenefitPlanNetPeriodicBenefitCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlanServiceCost": { "auth_ref": [ "r245", "r250", "r261", "r267" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails": { "order": 1.0, "parentTag": "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.", "label": "Defined Benefit Plan, Service Cost", "terseLabel": "Service cost" } } }, "localname": "DefinedBenefitPlanServiceCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable": { "auth_ref": [ "r256", "r257", "r258", "r259", "r267" ], "lang": { "en-US": { "role": { "documentation": "Disclosures and provisions pertaining to defined benefit pension plans or other postretirement defined benefit plans. The arrangements are generally based on terms and conditions stipulated by the entity, and which contain a promise by the employer to pay certain amounts or awards at designated future dates, including a period after retirement, upon compliance with stipulated requirements. Excludes disclosures pertaining to defined contribution plans.", "label": "Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table]" } } }, "localname": "DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]", "terseLabel": "Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]" } } }, "localname": "DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DefinedContributionPlanCostRecognized": { "auth_ref": [ "r268" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost for defined contribution plan.", "label": "Defined Contribution Plan, Cost", "terseLabel": "Employer contributions" } } }, "localname": "DefinedContributionPlanCostRecognized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNarrativeDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DepreciationAndAmortization": { "auth_ref": [ "r128", "r197" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 5.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.", "label": "Depreciation, Depletion and Amortization, Nonproduction", "terseLabel": "Depreciation and amortization" } } }, "localname": "DepreciationAndAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DepreciationDepletionAndAmortization": { "auth_ref": [ "r128", "r159" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 2.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.", "label": "Depreciation, Depletion and Amortization", "terseLabel": "Depreciation and amortization" } } }, "localname": "DepreciationDepletionAndAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeAssetsCurrent": { "auth_ref": [ "r79" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 6.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Asset, Current", "terseLabel": "Derivative instruments" } } }, "localname": "DerivativeAssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeAssetsNoncurrent": { "auth_ref": [ "r79" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 4.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Asset, Noncurrent", "terseLabel": "Derivative instruments" } } }, "localname": "DerivativeAssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeContractTypeDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Financial instrument or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.", "label": "Derivative Contract [Domain]", "terseLabel": "Derivative Contract [Domain]" } } }, "localname": "DerivativeContractTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral": { "auth_ref": [ "r79", "r80", "r81", "r341" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.", "label": "Derivative Asset, Fair Value, Amount Not Offset Against Collateral", "verboseLabel": "Derivative Asset, Fair Value, Amount Not Offset Against Collateral" } } }, "localname": "DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral": { "auth_ref": [ "r79", "r80", "r81", "r341" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.", "label": "Derivative Liability, Fair Value, Amount Not Offset Against Collateral", "terseLabel": "Derivative liability" } } }, "localname": "DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeFairValueOfDerivativeNet": { "auth_ref": [ "r348" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value of the assets less the liabilities of a derivative or group of derivatives.", "label": "Derivative, Fair Value, Net", "terseLabel": "Derivative, Fair Value, Net" } } }, "localname": "DerivativeFairValueOfDerivativeNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeGainOnDerivative": { "auth_ref": [ "r327" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase in the fair value of derivatives recognized in the income statement.", "label": "Derivative, Gain on Derivative", "terseLabel": "Derivative, Gain on Derivative" } } }, "localname": "DerivativeGainOnDerivative", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeInstrumentRiskAxis": { "auth_ref": [ "r326", "r328", "r331", "r335" ], "lang": { "en-US": { "role": { "documentation": "Information by type of derivative contract.", "label": "Derivative Instrument [Axis]", "terseLabel": "Derivative Instrument [Axis]" } } }, "localname": "DerivativeInstrumentRiskAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Derivative Instruments and Hedging Activities Disclosure [Abstract]" } } }, "localname": "DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock": { "auth_ref": [ "r344" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.", "label": "Derivative Instruments and Hedging Activities Disclosure [Text Block]", "terseLabel": "Derivative Instruments" } } }, "localname": "DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstruments" ], "xbrltype": "textBlockItemType" }, "us-gaap_DerivativeLiabilitiesCurrent": { "auth_ref": [ "r79" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 7.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Liability, Current", "terseLabel": "Derivative instruments" } } }, "localname": "DerivativeLiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeLiabilitiesNoncurrent": { "auth_ref": [ "r79" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 4.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Liability, Noncurrent", "terseLabel": "Derivative instruments" } } }, "localname": "DerivativeLiabilitiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Derivative [Line Items]", "terseLabel": "Derivative [Line Items]" } } }, "localname": "DerivativeLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DerivativeLossOnDerivative": { "auth_ref": [ "r327" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of decrease in the fair value of derivatives recognized in the income statement.", "label": "Derivative, Loss on Derivative", "negatedTerseLabel": "Derivative, Loss on Derivative", "terseLabel": "Derivative, Loss on Derivative" } } }, "localname": "DerivativeLossOnDerivative", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeNonmonetaryNotionalAmount": { "auth_ref": [ "r320", "r322" ], "lang": { "en-US": { "role": { "documentation": "Nominal number of units used to calculate payment on derivative.", "label": "Derivative, Nonmonetary Notional Amount", "terseLabel": "Derivative, Nonmonetary Notional Amount" } } }, "localname": "DerivativeNonmonetaryNotionalAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "decimalItemType" }, "us-gaap_DerivativeNotionalAmount": { "auth_ref": [ "r320", "r322" ], "lang": { "en-US": { "role": { "documentation": "Nominal or face amount used to calculate payment on derivative.", "label": "Derivative, Notional Amount", "terseLabel": "Derivative, Notional Amount" } } }, "localname": "DerivativeNotionalAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeTable": { "auth_ref": [ "r139", "r319", "r321", "r322", "r323", "r324", "r330", "r331", "r340", "r342", "r343" ], "lang": { "en-US": { "role": { "documentation": "Schedule that describes and identifies a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.", "label": "Derivative [Table]", "terseLabel": "Derivative [Table]" } } }, "localname": "DerivativeTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsFairValueDetails", "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisaggregationOfRevenueLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Disaggregation of Revenue [Line Items]", "terseLabel": "Disaggregation of Revenue [Line Items]" } } }, "localname": "DisaggregationOfRevenueLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisaggregationOfRevenueTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor.", "label": "Disaggregation of Revenue [Table]", "terseLabel": "Disaggregation of Revenue [Table]" } } }, "localname": "DisaggregationOfRevenueTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisaggregationOfRevenueTableTextBlock": { "auth_ref": [ "r235" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor.", "label": "Disaggregation of Revenue [Table Text Block]", "terseLabel": "Disaggregation of Revenue" } } }, "localname": "DisaggregationOfRevenueTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock": { "auth_ref": [ "r285" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for share-based payment arrangement.", "label": "Share-based Payment Arrangement [Text Block]", "terseLabel": "Stock-Based Compensation" } } }, "localname": "DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensation" ], "xbrltype": "textBlockItemType" }, "us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Share-based Payment Arrangement [Abstract]" } } }, "localname": "DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax": { "auth_ref": [ "r5", "r6", "r7", "r8", "r9", "r17", "r100", "r420" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 1.0, "parentTag": "us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.", "label": "Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax", "totalLabel": "Loss from discontinued operations before income tax" } } }, "localname": "DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation.", "label": "Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share", "terseLabel": "Basic (in dollars per share)" } } }, "localname": "DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation.", "label": "Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share", "terseLabel": "Diluted (in dollars per share)" } } }, "localname": "DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation": { "auth_ref": [ "r6", "r7", "r8", "r9", "r17", "r23", "r288", "r294" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 2.0, "parentTag": "us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.", "label": "Discontinued Operation, Tax Effect of Discontinued Operation", "terseLabel": "Income tax benefit" } } }, "localname": "DiscontinuedOperationTaxEffectOfDiscontinuedOperation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Discontinued Operations and Disposal Groups [Abstract]" } } }, "localname": "DiscontinuedOperationsAndDisposalGroupsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DiscontinuedOperationsHeldForSaleOrDisposedOfBySaleMember": { "auth_ref": [ "r2", "r3", "r4" ], "lang": { "en-US": { "role": { "documentation": "Component or group of components classified as held-for-sale or disposed of by sale and representing a strategic shift that has or will have a major effect on operations and financial results. Includes a business or nonprofit activity on acquisition classified as held-for-sale.", "label": "Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]", "terseLabel": "Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]" } } }, "localname": "DiscontinuedOperationsHeldForSaleOrDisposedOfBySaleMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DiscontinuedOperationsHeldforsaleMember": { "auth_ref": [ "r2", "r4", "r22" ], "lang": { "en-US": { "role": { "documentation": "Component or group of components classified as held-for-sale and representing a strategic shift that has or will have a major effect on operations and financial results. Includes a business or nonprofit activity on acquisition classified as held-for-sale.", "label": "Discontinued Operations, Held-for-sale [Member]", "terseLabel": "Discontinued Operations, Held-for-sale [Member]" } } }, "localname": "DiscontinuedOperationsHeldforsaleMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DisposalGroupClassificationAxis": { "auth_ref": [ "r22" ], "lang": { "en-US": { "role": { "documentation": "Information by disposal group classification.", "label": "Disposal Group Classification [Axis]", "terseLabel": "Disposal Group Classification [Axis]" } } }, "localname": "DisposalGroupClassificationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisposalGroupClassificationDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Component or group of components disposed of, including but not limited to, disposal group held-for-sale or disposed of by sale, disposed of by means other than sale, and discontinued operations.", "label": "Disposal Group Classification [Domain]", "terseLabel": "Disposal Group Classification [Domain]" } } }, "localname": "DisposalGroupClassificationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet": { "auth_ref": [ "r0", "r1", "r20", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 1.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.", "label": "Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net", "terseLabel": "Accounts receivable" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent": { "auth_ref": [ "r0", "r1", "r20", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 1.0, "parentTag": "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount classified as accounts payable attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Accounts Payable, Current", "terseLabel": "Accounts payable" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationClassifiedBalanceSheetDisclosuresAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Disposal Group, Including Discontinued Operation, Classified Balance Sheet Disclosures [Abstract]", "terseLabel": "Disposal Group, Including Discontinued Operation, Classified Balance Sheet Disclosures [Abstract]" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationClassifiedBalanceSheetDisclosuresAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization": { "auth_ref": [ "r18" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 2.0, "parentTag": "nwn_TotalExpensesDiscontinuedOperations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.", "label": "Disposal Group, Including Discontinued Operation, Depreciation and Amortization", "terseLabel": "Depreciation and amortization" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense": { "auth_ref": [ "r18" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 4.0, "parentTag": "nwn_TotalExpensesDiscontinuedOperations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of general and administrative expense attributable to disposal group, including, but not limited to, discontinued operation.", "label": "Disposal Group, Including Discontinued Operation, General and Administrative Expense", "terseLabel": "General taxes" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent": { "auth_ref": [ "r0", "r1", "r20", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 2.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as inventory attributable to disposal group, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Inventory, Current", "terseLabel": "Inventories" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationInventoryCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingExpense": { "auth_ref": [ "r18" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 1.0, "parentTag": "nwn_TotalExpensesDiscontinuedOperations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.", "label": "Disposal Group, Including Discontinued Operation, Operating Expense", "terseLabel": "Operations and maintenance" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOperatingExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets": { "auth_ref": [ "r0", "r1", "r20", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 3.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as other assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Other Assets, Current", "terseLabel": "Other current assets" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities": { "auth_ref": [ "r0", "r1", "r20", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 2.0, "parentTag": "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount classified as other liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Other Liabilities, Current", "terseLabel": "Other current liabilities" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherExpense": { "auth_ref": [ "r18" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 3.0, "parentTag": "nwn_TotalExpensesDiscontinuedOperations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of other expense attributable to disposal group, including, but not limited to, discontinued operation.", "label": "Disposal Group, Including Discontinued Operation, Other Expense", "terseLabel": "Other expenses and interest" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOtherExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets": { "auth_ref": [ "r0", "r1", "r20", "r195", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 7.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as other assets attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent", "terseLabel": "Other non-current assets" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities": { "auth_ref": [ "r0", "r1", "r20", "r195", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 4.0, "parentTag": "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount classified as other liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of beyond one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent", "terseLabel": "Other non-current liabilities" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent": { "auth_ref": [ "r0", "r1", "r20", "r195", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 4.0, "parentTag": "us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent", "terseLabel": "Property, plant, and equipment" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue": { "auth_ref": [ "r18" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": 1.0, "parentTag": "us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.", "label": "Disposal Group, Including Discontinued Operation, Revenue", "terseLabel": "Revenues" } } }, "localname": "DisposalGroupIncludingDiscontinuedOperationRevenue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]", "terseLabel": "Discontinued Operation, Income Statement Disclosures [Abstract]" } } }, "localname": "DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock": { "auth_ref": [ "r27", "r207" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.", "label": "Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]", "terseLabel": "Discontinued Operations" } } }, "localname": "DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperations", "http://www.nwnatural.com/role/DiscontinuedOperationsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of disposal group.", "label": "Disposal Group Name [Domain]", "terseLabel": "Disposal Group Name [Domain]" } } }, "localname": "DisposalGroupsIncludingDiscontinuedOperationsNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "domainItemType" }, "us-gaap_DividendsCommonStockCash": { "auth_ref": [ "r231" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.", "label": "Dividends, Common Stock, Cash", "negatedTerseLabel": "Dividends on common stock" } } }, "localname": "DividendsCommonStockCash", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_DueFromAffiliateCurrent": { "auth_ref": [ "r75", "r138", "r379", "r380", "r381", "r382" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 12.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).", "label": "Due from Affiliate, Current", "terseLabel": "Receivables from affiliates" } } }, "localname": "DueFromAffiliateCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DueToAffiliateCurrent": { "auth_ref": [ "r45", "r135", "r379", "r428" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 11.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Due to Affiliate, Current", "terseLabel": "Payables to affiliates" } } }, "localname": "DueToAffiliateCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_EarningsPerShareAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Earnings Per Share [Abstract]", "terseLabel": "Earnings (loss) per share of common stock:" } } }, "localname": "EarningsPerShareAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "stringItemType" }, "us-gaap_EarningsPerShareBasic": { "auth_ref": [ "r102", "r143", "r146", "r148", "r149", "r150", "r153", "r405", "r422" ], "lang": { "en-US": { "role": { "documentation": "The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.", "label": "Earnings Per Share, Basic", "terseLabel": "Basic (in dollars per share)" } } }, "localname": "EarningsPerShareBasic", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_EarningsPerShareDiluted": { "auth_ref": [ "r102", "r143", "r146", "r148", "r149", "r150", "r153", "r405", "r422" ], "lang": { "en-US": { "role": { "documentation": "The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.", "label": "Earnings Per Share, Diluted", "terseLabel": "Diluted (in dollars per share)" } } }, "localname": "EarningsPerShareDiluted", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_EarningsPerShareDilutedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Earnings Per Share, Diluted [Abstract]", "terseLabel": "Earnings (loss) per share of common stock" } } }, "localname": "EarningsPerShareDilutedAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_EarningsPerShareTextBlock": { "auth_ref": [ "r154" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for earnings per share.", "label": "Earnings Per Share [Text Block]", "terseLabel": "Earnings Per Share" } } }, "localname": "EarningsPerShareTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EarningsPerShare" ], "xbrltype": "textBlockItemType" }, "us-gaap_EffectiveIncomeTaxRateContinuingOperations": { "auth_ref": [ "r137", "r289", "r290" ], "lang": { "en-US": { "role": { "documentation": "Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.", "label": "Effective Income Tax Rate Reconciliation, Percent", "terseLabel": "Effective tax rate for continuing operations" } } }, "localname": "EffectiveIncomeTaxRateContinuingOperations", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "percentItemType" }, "us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate": { "auth_ref": [ "r289", "r290", "r292" ], "lang": { "en-US": { "role": { "documentation": "Percentage of domestic federal statutory tax rate applicable to pretax income (loss).", "label": "Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent", "terseLabel": "Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent" } } }, "localname": "EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "percentItemType" }, "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized": { "auth_ref": [ "r281" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost not yet recognized for nonvested award under share-based payment arrangement.", "label": "Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount", "terseLabel": "Unrecognized compensation costs" } } }, "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EnvironmentalExitCostsAnticipatedCost": { "auth_ref": [ "r221" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.", "label": "Environmental Exit Costs, Anticipated Cost", "terseLabel": "Environmental Exit Costs, Anticipated Cost" } } }, "localname": "EnvironmentalExitCostsAnticipatedCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EnvironmentalExitCostsCostsAccruedToDate": { "auth_ref": [ "r221" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of the liability for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.", "label": "Environmental Exit Costs, Costs Accrued to Date", "terseLabel": "Site Contingency, Environmental Remediation Costs Recognized" } } }, "localname": "EnvironmentalExitCostsCostsAccruedToDate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EnvironmentalLossContingencyDisclosureTextBlock": { "auth_ref": [ "r215" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for environmental loss contingencies, such as presence of hazardous waste, relevant information from reports issued by regulators, and estimated costs to achieve compliance with regulatory requirements. This element may be used for all of an entity's disclosures about environmental loss contingencies.", "label": "Environmental Loss Contingency Disclosure [Text Block]", "terseLabel": "Environmental Matters" } } }, "localname": "EnvironmentalLossContingencyDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMatters" ], "xbrltype": "textBlockItemType" }, "us-gaap_EnvironmentalRemediationExpense": { "auth_ref": [ "r208", "r212" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 8.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 }, "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 3.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 }, "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 3.0, "parentTag": "us-gaap_GrossProfit", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.", "label": "Environmental Remediation Expense", "terseLabel": "Environmental remediation", "verboseLabel": "Amortization of environmental remediation" } } }, "localname": "EnvironmentalRemediationExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EnvironmentalRemediationObligationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Environmental Remediation Obligations [Abstract]" } } }, "localname": "EnvironmentalRemediationObligationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_EnvironmentalRemediationSiteAxis": { "auth_ref": [ "r209", "r211", "r213", "r214", "r220" ], "lang": { "en-US": { "role": { "documentation": "Information by location or named area designated for environmental remediation.", "label": "Environmental Remediation Site [Axis]", "terseLabel": "Environmental Remediation Site [Axis]" } } }, "localname": "EnvironmentalRemediationSiteAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_EnvironmentalRemediationSiteDomain": { "auth_ref": [ "r209" ], "lang": { "en-US": { "role": { "documentation": "Location or named area designated for environmental remediation.", "label": "Environmental Remediation Site [Domain]", "terseLabel": "Environmental Remediation Site [Domain]" } } }, "localname": "EnvironmentalRemediationSiteDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_EnvironmentalRestorationCostsMember": { "auth_ref": [ "r438" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of costs associated with site remediation or other environmental exit costs that may occur on the sale, disposal, abandonment or decommissioning of a property.", "label": "Environmental Restoration Costs [Member]", "terseLabel": "Environmental costs [Member]" } } }, "localname": "EnvironmentalRestorationCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_EquityComponentDomain": { "auth_ref": [ "r226" ], "lang": { "en-US": { "role": { "documentation": "Components of equity are the parts of the total Equity balance including that which is allocated to common, preferred, treasury stock, retained earnings, etc.", "label": "Equity Component [Domain]", "terseLabel": "Equity Component [Domain]" } } }, "localname": "EquityComponentDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_EquityMethodInvestmentOwnershipPercentage": { "auth_ref": [ "r177" ], "lang": { "en-US": { "role": { "documentation": "The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.", "label": "Equity Method Investment, Ownership Percentage", "terseLabel": "Ownership percentage of TWH" } } }, "localname": "EquityMethodInvestmentOwnershipPercentage", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "percentItemType" }, "us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal": { "auth_ref": [ "r103", "r104", "r128" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of gain (loss) on sale or disposal of an equity method investment.", "label": "Equity Method Investment, Realized Gain (Loss) on Disposal", "terseLabel": "Equity Method Investment, Realized Gain (Loss) on Disposal" } } }, "localname": "EquityMethodInvestmentRealizedGainLossOnDisposal", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets": { "auth_ref": [ "r178" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.", "label": "Equity Method Investment, Underlying Equity in Net Assets", "terseLabel": "Investment balance in TWH" } } }, "localname": "EquityMethodInvestmentUnderlyingEquityInNetAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_EquitySecuritiesByIndustryAxis": { "auth_ref": [ "r188" ], "lang": { "en-US": { "role": { "documentation": "Information by industry sector, examples include but are not limited to, commercial, industrial, agricultural, financial services, technology, healthcare and real estate.", "label": "Industry Sector [Axis]", "terseLabel": "Industry Sector [Axis]" } } }, "localname": "EquitySecuritiesByIndustryAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "stringItemType" }, "us-gaap_EquitySecuritiesIndustryMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Industry sector consisting of government, private and corporate entities engaged in business activities, including but not limited to, commercial, industrial, agricultural, financial services, technology, healthcare and real estate.", "label": "Industry Sector [Domain]", "terseLabel": "Industry Sector [Domain]" } } }, "localname": "EquitySecuritiesIndustryMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesCreditLossesAsu201613Details" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain": { "auth_ref": [ "r346" ], "lang": { "en-US": { "role": { "documentation": "Class of asset.", "label": "Asset Class [Domain]", "terseLabel": "Asset Class [Domain]" } } }, "localname": "FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueByAssetClassAxis": { "auth_ref": [ "r345", "r347" ], "lang": { "en-US": { "role": { "documentation": "Information by class of asset.", "label": "Asset Class [Axis]", "terseLabel": "Asset Class [Axis]" } } }, "localname": "FairValueByAssetClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "stringItemType" }, "us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths": { "auth_ref": [ "r370" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in next fiscal year following latest fiscal year.", "label": "Finance Lease, Liability, Payments, Due Next Twelve Months", "terseLabel": "Finance Lease, Liability, Payments, Due Next Twelve Months" } } }, "localname": "FinanceLeaseLiabilityPaymentsDueNextTwelveMonths", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinanceLeasePrincipalPayments": { "auth_ref": [ "r358", "r365" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow for principal payment on finance lease.", "label": "Finance Lease, Principal Payments", "terseLabel": "Finance Lease, Principal Payments" } } }, "localname": "FinanceLeasePrincipalPayments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinanceLeaseRightOfUseAsset": { "auth_ref": [ "r355" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's right to use underlying asset under finance lease.", "label": "Finance Lease, Right-of-Use Asset", "terseLabel": "Finance Lease, Right-of-Use Asset" } } }, "localname": "FinanceLeaseRightOfUseAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ForeignExchangeContractMember": { "auth_ref": [ "r248", "r332" ], "lang": { "en-US": { "role": { "documentation": "Derivative instrument whose primary underlying risk is tied to foreign exchange rates.", "label": "Foreign Exchange Contract [Member]", "terseLabel": "Foreign exchange", "verboseLabel": "Foreign Exchange Contract [Member]" } } }, "localname": "ForeignExchangeContractMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_GainLossOnDerivativeInstrumentsNetPretax": { "auth_ref": [ "r326" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.", "label": "Gain (Loss) on Derivative Instruments, Net, Pretax", "negatedTerseLabel": "Gain (Loss) on Derivative Instruments, Net, Pretax" } } }, "localname": "GainLossOnDerivativeInstrumentsNetPretax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_Goodwill": { "auth_ref": [ "r189", "r191" ], "calculation": { "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails": { "order": 3.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 }, "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 8.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.", "label": "Goodwill", "terseLabel": "Goodwill" } } }, "localname": "Goodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails", "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_GoodwillImpairmentLoss": { "auth_ref": [ "r128", "r190", "r192", "r194" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.", "label": "Goodwill, Impairment Loss", "terseLabel": "Goodwill, Impairment Loss" } } }, "localname": "GoodwillImpairmentLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_GrossProfit": { "auth_ref": [ "r105" ], "calculation": { "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.", "label": "Gross Profit", "totalLabel": "NGD margin" } } }, "localname": "GrossProfit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeLossFromContinuingOperations": { "auth_ref": [ "r106", "r129", "r150", "r310" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_NetIncomeLoss", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after tax of income (loss) from continuing operations attributable to the parent.", "label": "Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent", "terseLabel": "Net income from continuing operations", "totalLabel": "Net income (loss) from continuing operations", "verboseLabel": "Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent" } } }, "localname": "IncomeLossFromContinuingOperations", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeLossFromContinuingOperationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]", "terseLabel": "Earnings from continuing operations per share of common stock:" } } }, "localname": "IncomeLossFromContinuingOperationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest": { "auth_ref": [ "r99", "r143", "r392", "r402", "r423" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperations", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.", "label": "Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest", "totalLabel": "Income (loss) before income taxes" } } }, "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeLossFromContinuingOperationsPerBasicShare": { "auth_ref": [ "r97", "r102", "r146", "r148", "r149", "r401", "r403", "r405", "r419" ], "lang": { "en-US": { "role": { "documentation": "The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.", "label": "Income (Loss) from Continuing Operations, Per Basic Share", "terseLabel": "Basic (in dollars per share)" } } }, "localname": "IncomeLossFromContinuingOperationsPerBasicShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare": { "auth_ref": [ "r97", "r102", "r146", "r148", "r149", "r150", "r405", "r419", "r422" ], "lang": { "en-US": { "role": { "documentation": "The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.", "label": "Income (Loss) from Continuing Operations, Per Diluted Share", "terseLabel": "Diluted (in dollars per share)" } } }, "localname": "IncomeLossFromContinuingOperationsPerDilutedShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic and Diluted Share [Abstract]", "terseLabel": "Loss from discontinued operations per share of common stock:", "verboseLabel": "Loss from discontinued operations per share of common stock" } } }, "localname": "IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity": { "auth_ref": [ "r5", "r6", "r7", "r8", "r9", "r17", "r23", "r311" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_NetIncomeLoss", "weight": 1.0 }, "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.", "label": "Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent", "terseLabel": "Loss from discontinued operations, net of tax", "totalLabel": "Loss from discontinued operations, net of tax", "verboseLabel": "Income (loss) from discontinued operations, net of tax" } } }, "localname": "IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeStatementAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income Statement [Abstract]" } } }, "localname": "IncomeStatementAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by name of disposal group.", "label": "Disposal Group Name [Axis]", "terseLabel": "Disposal Group Name [Axis]" } } }, "localname": "IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]", "terseLabel": "Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]", "verboseLabel": "Income Statement [Line Items]" } } }, "localname": "IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable": { "auth_ref": [ "r1", "r11", "r12", "r13", "r14", "r15", "r16", "r21", "r24", "r25", "r26", "r205", "r206" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.", "label": "Disposal Groups, Including Discontinued Operations [Table]", "terseLabel": "Disposal Groups, Including Discontinued Operations [Table]" } } }, "localname": "IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails", "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementLocationAxis": { "auth_ref": [ "r202" ], "lang": { "en-US": { "role": { "documentation": "Information by location in the income statement.", "label": "Income Statement Location [Axis]", "terseLabel": "Income Statement Location [Axis]" } } }, "localname": "IncomeStatementLocationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementLocationDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Location in the income statement.", "label": "Income Statement Location [Domain]", "terseLabel": "Income Statement Location [Domain]" } } }, "localname": "IncomeStatementLocationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_IncomeTaxDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income Tax Disclosure [Abstract]" } } }, "localname": "IncomeTaxDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_IncomeTaxDisclosureTextBlock": { "auth_ref": [ "r295" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.", "label": "Income Tax Disclosure [Text Block]", "verboseLabel": "Income Tax" } } }, "localname": "IncomeTaxDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTax" ], "xbrltype": "textBlockItemType" }, "us-gaap_IncomeTaxExpenseBenefit": { "auth_ref": [ "r134", "r160", "r293" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperations", "weight": -1.0 }, "http://www.nwnatural.com/role/IncomeTaxDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.", "label": "Income Tax Expense (Benefit)", "totalLabel": "Total provision for income taxes on continuing operations", "verboseLabel": "Income tax expense (benefit)" } } }, "localname": "IncomeTaxExpenseBenefit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Effective Income Tax Rate Reconciliation, Amount [Abstract]" } } }, "localname": "IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate": { "auth_ref": [ "r133", "r289", "r290" ], "calculation": { "http://www.nwnatural.com/role/IncomeTaxDetails": { "order": 1.0, "parentTag": "us-gaap_IncomeTaxExpenseBenefit", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.", "label": "Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount", "terseLabel": "Income taxes at statutory rates (federal and state)" } } }, "localname": "IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxReconciliationOtherAdjustments": { "auth_ref": [ "r289" ], "calculation": { "http://www.nwnatural.com/role/IncomeTaxDetails": { "order": 4.0, "parentTag": "us-gaap_IncomeTaxExpenseBenefit", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.", "label": "Effective Income Tax Rate Reconciliation, Other Adjustments, Amount", "terseLabel": "Other, net" } } }, "localname": "IncomeTaxReconciliationOtherAdjustments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes": { "auth_ref": [ "r133", "r289", "r290" ], "calculation": { "http://www.nwnatural.com/role/IncomeTaxDetails": { "order": 2.0, "parentTag": "us-gaap_IncomeTaxExpenseBenefit", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit).", "label": "Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount", "terseLabel": "Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount" } } }, "localname": "IncomeTaxReconciliationStateAndLocalIncomeTaxes", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxesPaidNet": { "auth_ref": [ "r131" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.", "label": "Income Taxes Paid, Net", "terseLabel": "Income taxes paid (refunded), net" } } }, "localname": "IncomeTaxesPaidNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxesReceivable": { "auth_ref": [ "r76", "r399", "r418" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 9.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.", "label": "Income Taxes Receivable, Current", "terseLabel": "Income Taxes Receivable, Current" } } }, "localname": "IncomeTaxesReceivable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInAccountsAndOtherReceivables": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 12.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the amount due from customers for the credit sale of goods and services; includes accounts receivable and other types of receivables.", "label": "Increase (Decrease) in Accounts and Other Receivables", "negatedTerseLabel": "Receivables, net" } } }, "localname": "IncreaseDecreaseInAccountsAndOtherReceivables", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInAccountsPayable": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 15.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.", "label": "Increase (Decrease) in Accounts Payable", "terseLabel": "Accounts payable" } } }, "localname": "IncreaseDecreaseInAccountsPayable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInAccruedTaxesPayable": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 14.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period of all taxes owed but not paid, including income, property and other taxes.", "label": "Increase (Decrease) in Accrued Taxes Payable", "terseLabel": "Income and other taxes" } } }, "localname": "IncreaseDecreaseInAccruedTaxesPayable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInDeferredGasCost": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 17.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in carrying amount of capitalized gas costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer.", "label": "Increase (Decrease) in Deferred Gas Cost", "negatedTerseLabel": "Deferred gas costs" } } }, "localname": "IncreaseDecreaseInDeferredGasCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInInterestPayableNet": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 16.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.", "label": "Increase (Decrease) in Interest Payable, Net", "terseLabel": "Interest accrued" } } }, "localname": "IncreaseDecreaseInInterestPayableNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInInventories": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 13.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.", "label": "Increase (Decrease) in Inventories", "negatedTerseLabel": "Inventories" } } }, "localname": "IncreaseDecreaseInInventories", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInOperatingCapitalAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Increase (Decrease) in Operating Capital [Abstract]", "terseLabel": "Changes in assets and liabilities:" } } }, "localname": "IncreaseDecreaseInOperatingCapitalAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 19.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in operating assets after deduction of operating liabilities classified as other.", "label": "Increase (Decrease) in Other Operating Assets and Liabilities, Net", "negatedTerseLabel": "Other, net" } } }, "localname": "IncreaseDecreaseInOtherOperatingCapitalNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInRegulatoryAssetsAndLiabilities": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 18.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the value of assets that are created when regulatory agencies permits public utilities to defer costs (revenues) to the balance sheet. This element is a the increase (decrease) of regulatory assets and liabilities combined.", "label": "Increase (Decrease) in Regulatory Assets and Liabilities", "negatedTerseLabel": "Decoupling mechanism" } } }, "localname": "IncreaseDecreaseInRegulatoryAssetsAndLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInRegulatoryLiabilities": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 9.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in regulated liabilities. Regulated liabilities are created when regulatory agency permits an entity to defer revenues to the balance sheet.", "label": "Increase (Decrease) in Regulatory Liabilities", "terseLabel": "Regulatory revenue recovery deferral from the TCJA" } } }, "localname": "IncreaseDecreaseInRegulatoryLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInStockholdersEquityRollForward": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.", "label": "Increase (Decrease) in Stockholders' Equity [Roll Forward]", "terseLabel": "Increase (Decrease) in Stockholders' Equity [Roll Forward]" } } }, "localname": "IncreaseDecreaseInStockholdersEquityRollForward", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "stringItemType" }, "us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements": { "auth_ref": [ "r147", "r152" ], "calculation": { "http://www.nwnatural.com/role/EarningsPerShareDetails": { "order": 2.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.", "label": "Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements", "terseLabel": "Additional shares for stock-based compensation plans" } } }, "localname": "IncrementalCommonSharesAttributableToShareBasedPaymentArrangements", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "sharesItemType" }, "us-gaap_InterestIncomeExpenseNonoperatingNet": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 3.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net amount of nonoperating interest income (expense).", "label": "Interest Income (Expense), Nonoperating, Net", "negatedTerseLabel": "Interest expense, net" } } }, "localname": "InterestIncomeExpenseNonoperatingNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestPaidNet": { "auth_ref": [ "r122", "r124", "r131" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.", "label": "Interest Paid, Excluding Capitalized Interest, Operating Activities", "terseLabel": "Interest paid, net of capitalization" } } }, "localname": "InterestPaidNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestPayableCurrent": { "auth_ref": [ "r34", "r35", "r68" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 5.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Interest Payable, Current", "terseLabel": "Interest accrued" } } }, "localname": "InterestPayableCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_InventoryGasInStorageUndergroundNoncurrent": { "auth_ref": [ "r64" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of natural gas stored underground in depleted gas reservoirs, aquifers, or salt caverns to meet future seasonal and peak load demands and also as insurance against unforeseen supply disruptions, and deemed to be a noncurrent asset because it is not expected to be used within 12 months or in the normal operating cycle.", "label": "Inventory, Gas in Storage Underground, Noncurrent", "terseLabel": "Gas reserves" } } }, "localname": "InventoryGasInStorageUndergroundNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_InvestmentTextBlock": { "auth_ref": [ "r175", "r176", "r180", "r181" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for investment.", "label": "Investment [Text Block]", "terseLabel": "Investments" } } }, "localname": "InvestmentTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/Investments" ], "xbrltype": "textBlockItemType" }, "us-gaap_InvestmentsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Investments [Abstract]" } } }, "localname": "InvestmentsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_LeaseCostTableTextBlock": { "auth_ref": [ "r369" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income.", "label": "Lease, Cost [Table Text Block]", "terseLabel": "Lease Expense" } } }, "localname": "LeaseCostTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_LeaseIncome": { "auth_ref": [ "r377" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.", "label": "Lease Income", "totalLabel": "Total lease revenue" } } }, "localname": "LeaseIncome", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LeasesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Leases [Abstract]" } } }, "localname": "LeasesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_LeasesOfLesseeDisclosureTextBlock": { "auth_ref": [ "r354" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.", "label": "Leases of Lessee Disclosure [Text Block]", "terseLabel": "Leases of Lessee Disclosure" } } }, "localname": "LeasesOfLesseeDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesNotes" ], "xbrltype": "textBlockItemType" }, "us-gaap_LesseeLeaseDescriptionLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Lessee, Lease, Description [Line Items]", "terseLabel": "Lessee, Lease, Description [Line Items]" } } }, "localname": "LesseeLeaseDescriptionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "stringItemType" }, "us-gaap_LesseeLeaseDescriptionTable": { "auth_ref": [ "r363" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about lessee's leases.", "label": "Lessee, Lease, Description [Table]", "terseLabel": "Lessee, Lease, Description [Table]" } } }, "localname": "LesseeLeaseDescriptionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "stringItemType" }, "us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedRenewalTerm1": { "auth_ref": [ "r362" ], "lang": { "en-US": { "role": { "documentation": "Term of lessee's operating lease renewal for lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Lessee, Operating Lease, Lease Not yet Commenced, Renewal Term", "terseLabel": "Lessee, Operating Lease, Lease Not yet Commenced, Renewal Term" } } }, "localname": "LesseeOperatingLeaseLeaseNotYetCommencedRenewalTerm1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "durationItemType" }, "us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1": { "auth_ref": [ "r362" ], "lang": { "en-US": { "role": { "documentation": "Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract", "terseLabel": "Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract" } } }, "localname": "LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "durationItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock": { "auth_ref": [ "r370" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of undiscounted cash flows of lessee's operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position.", "label": "Lessee, Operating Lease, Liability, Maturity [Table Text Block]", "terseLabel": "Lessee, Operating Lease, Liability, Maturity" } } }, "localname": "LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease.", "label": "Lessee, Operating Lease, Liability, Payments, Due", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due", "totalLabel": "Lessee, Operating Lease, Liability, Payments, Due" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 5.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Due after Year Five", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due after Year Five" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 4.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Due Year Five", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due Year Five" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 3.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Due Year Four", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due Year Four" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFour", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 2.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Due Year Three", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due Year Three" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearThree", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 1.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Due Year Two", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Due Year Two" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearTwo", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear": { "auth_ref": [ "r370" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 6.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.", "label": "Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year", "terseLabel": "Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount": { "auth_ref": [ "r370" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.", "label": "Lessee, Operating Lease, Liability, Undiscounted Excess Amount", "terseLabel": "Lessee, Operating Lease, Liability, Undiscounted Excess Amount" } } }, "localname": "LesseeOperatingLeaseLiabilityUndiscountedExcessAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseTermOfContract": { "auth_ref": [ "r361" ], "lang": { "en-US": { "role": { "documentation": "Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Lessee, Operating Lease, Term of Contract", "terseLabel": "Lessee, Operating Lease, Term of Contract" } } }, "localname": "LesseeOperatingLeaseTermOfContract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "durationItemType" }, "us-gaap_LessorLeaseDescriptionLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Lessor, Lease, Description [Line Items]", "terseLabel": "Lessor, Lease, Description [Line Items]" } } }, "localname": "LessorLeaseDescriptionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "us-gaap_LessorLeaseDescriptionTable": { "auth_ref": [ "r376" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about lessor's leases.", "label": "Lessor, Lease, Description [Table]", "terseLabel": "Lessor, Lease, Description [Table]" } } }, "localname": "LessorLeaseDescriptionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "stringItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceived": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor for operating lease.", "label": "Lessor, Operating Lease, Payments to be Received", "totalLabel": "Total lease revenue" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceived", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedFiveYears": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 5.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor in fifth fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Five Years", "terseLabel": "Operating Lease, Payments to be Received, Five Years" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedFiveYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedFourYears": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 4.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor in fourth year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Four Years", "terseLabel": "Operating Lease, Payments to be Received, Four Years" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedFourYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedMaturityTableTextBlock": { "auth_ref": [ "r374" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of maturity of undiscounted cash flows to be received by lessor on annual basis for operating lease.", "label": "Lessor, Operating Lease, Payments to be Received, Maturity [Table Text Block]", "terseLabel": "Lessor, Operating Lease, Payments to be Received, Maturity" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedMaturityTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 1.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor in remainder of fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year", "terseLabel": "Operating Lease, Payments to be Received, Remainder of Fiscal Year" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedThereafter": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 6.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor after fifth fiscal year following latest statement of financial position date for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Thereafter", "terseLabel": "Operating Lease, Payments to be Received, Thereafter" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedThereafter", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedThreeYears": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 3.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor in third fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Three Years", "terseLabel": "Operating Lease, Payments to be Received, Three Years" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedThreeYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorOperatingLeasePaymentsToBeReceivedTwoYears": { "auth_ref": [ "r374" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 2.0, "parentTag": "us-gaap_LessorOperatingLeasePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lease payments to be received by lessor in second fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.", "label": "Lessor, Operating Lease, Payments to be Received, Two Years", "terseLabel": "Operating Lease, Payments to be Received, Two Years" } } }, "localname": "LessorOperatingLeasePaymentsToBeReceivedTwoYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LessorSalesTypeLeaseRenewalTerm1": { "auth_ref": [ "r375" ], "lang": { "en-US": { "role": { "documentation": "Term of lessor's sales-type lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Lessor, Sales-type Lease, Renewal Term", "terseLabel": "Lessor, Sales-type Lease, Renewal Term" } } }, "localname": "LessorSalesTypeLeaseRenewalTerm1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "durationItemType" }, "us-gaap_LessorSalesTypeLeaseTermOfContract1": { "auth_ref": [ "r375" ], "lang": { "en-US": { "role": { "documentation": "Term of lessor's sales-type lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Lessor, Sales-type Lease, Term of Contract", "terseLabel": "Lessor, Sales-type Lease, Term of Contract" } } }, "localname": "LessorSalesTypeLeaseTermOfContract1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "durationItemType" }, "us-gaap_LiabilitiesAndStockholdersEquity": { "auth_ref": [ "r56", "r398", "r414" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.", "label": "Liabilities and Equity", "totalLabel": "Total liabilities and equity" } } }, "localname": "LiabilitiesAndStockholdersEquity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesAndStockholdersEquityAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Liabilities and Equity [Abstract]", "terseLabel": "Liabilities and equity:" } } }, "localname": "LiabilitiesAndStockholdersEquityAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_LiabilitiesCurrent": { "auth_ref": [ "r69" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.", "label": "Liabilities, Current", "totalLabel": "Total current liabilities" } } }, "localname": "LiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesCurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Liabilities, Current [Abstract]", "terseLabel": "Current liabilities:" } } }, "localname": "LiabilitiesCurrentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation": { "auth_ref": [ "r0", "r1", "r20", "r22", "r203" ], "calculation": { "http://www.nwnatural.com/role/DiscontinuedOperationsDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount classified as liabilities attributable to disposal group held for sale or disposed of.", "label": "Disposal Group, Including Discontinued Operation, Liabilities", "totalLabel": "Total discontinued operations liabilities" } } }, "localname": "LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent": { "auth_ref": [ "r0", "r1", "r20", "r22", "r196", "r203" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 10.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.", "label": "Disposal Group, Including Discontinued Operation, Liabilities, Current", "terseLabel": "Discontinued operations current liabilities" } } }, "localname": "LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LineOfCreditMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time, and under which borrowings outstanding may be either short-term or long-term, depending upon the particulars.", "label": "Line of Credit [Member]", "terseLabel": "Line of Credit [Member]" } } }, "localname": "LineOfCreditMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "domainItemType" }, "us-gaap_LongTermDebt": { "auth_ref": [ "r49", "r224", "r397", "r412" ], "calculation": { "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetailsCalc2": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.", "label": "Long-term Debt", "terseLabel": "Long-term Debt", "totalLabel": "Carrying amount" } } }, "localname": "LongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_LongTermDebtCurrent": { "auth_ref": [ "r67" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.", "label": "Long-term Debt, Current Maturities", "terseLabel": "Current maturities of long-term debt" } } }, "localname": "LongTermDebtCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LongTermDebtNoncurrent": { "auth_ref": [ "r71" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.", "label": "Long-term Debt, Excluding Current Maturities", "terseLabel": "Long-term debt" } } }, "localname": "LongTermDebtNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LongtermDebtWeightedAverageInterestRate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Weighted average interest rate of long-term debt outstanding calculated at point in time.", "label": "Long-term Debt, Weighted Average Interest Rate, at Point in Time", "terseLabel": "Weighted average interest rate" } } }, "localname": "LongtermDebtWeightedAverageInterestRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "percentItemType" }, "us-gaap_NetCashProvidedByUsedInFinancingActivities": { "auth_ref": [ "r123" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 3.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.", "label": "Net Cash Provided by (Used in) Financing Activities", "totalLabel": "Net Cash Provided by (Used in) Financing Activities" } } }, "localname": "NetCashProvidedByUsedInFinancingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]", "terseLabel": "Financing activities:" } } }, "localname": "NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetCashProvidedByUsedInInvestingActivities": { "auth_ref": [ "r123" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 2.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.", "label": "Net Cash Provided by (Used in) Investing Activities", "totalLabel": "Cash used in investing activities" } } }, "localname": "NetCashProvidedByUsedInInvestingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]", "terseLabel": "Investing activities:" } } }, "localname": "NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetCashProvidedByUsedInOperatingActivities": { "auth_ref": [ "r123", "r126", "r129" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 1.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.", "label": "Net Cash Provided by (Used in) Operating Activities", "totalLabel": "Cash provided by operating activities" } } }, "localname": "NetCashProvidedByUsedInOperatingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]", "terseLabel": "Operating activities:" } } }, "localname": "NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetIncomeLoss": { "auth_ref": [ "r91", "r93", "r101", "r129", "r152", "r404", "r421" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 1.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 }, "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.", "label": "Net Income (Loss) Attributable to Parent", "terseLabel": "Net income", "totalLabel": "Net income (loss)" } } }, "localname": "NetIncomeLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.", "label": "New Accounting Pronouncements, Policy [Policy Text Block]", "terseLabel": "New Accounting Standards" } } }, "localname": "NewAccountingPronouncementsPolicyPolicyTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_NotesReceivableMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) within one year of the balance sheet date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics.", "label": "Notes Receivable [Member]", "terseLabel": "Notes Receivable [Member]" } } }, "localname": "NotesReceivableMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_NumberOfBusinessesAcquired": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The number of businesses acquired by the entity during the period.", "label": "Number of Businesses Acquired", "terseLabel": "Number of Businesses Acquired" } } }, "localname": "NumberOfBusinessesAcquired", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "integerItemType" }, "us-gaap_NumberOfReportableSegments": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.", "label": "Number of Reportable Segments", "terseLabel": "Number of Reportable Segments" } } }, "localname": "NumberOfReportableSegments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails" ], "xbrltype": "integerItemType" }, "us-gaap_OperatingCostsAndExpenses": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.", "label": "Operating Costs and Expenses", "terseLabel": "Operations and maintenance" } } }, "localname": "OperatingCostsAndExpenses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingExpenses": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_OperatingIncomeLoss", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.", "label": "Operating Expenses", "totalLabel": "Total operating expenses" } } }, "localname": "OperatingExpenses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingExpensesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Operating Expenses [Abstract]", "terseLabel": "Operating expenses:" } } }, "localname": "OperatingExpensesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "stringItemType" }, "us-gaap_OperatingIncomeLoss": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net result for the period of deducting operating expenses from operating revenues.", "label": "Operating Income (Loss)", "totalLabel": "Income from operations", "verboseLabel": "Income from operations" } } }, "localname": "OperatingIncomeLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseExpense": { "auth_ref": [ "r357" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of operating lease expense. Excludes sublease income.", "label": "Operating Lease, Expense", "terseLabel": "Operating Lease, Expense" } } }, "localname": "OperatingLeaseExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLeaseIncome": { "auth_ref": [ "r155", "r372", "r377" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 1.0, "parentTag": "us-gaap_LeaseIncome", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.", "label": "Operating Lease, Lease Income", "terseLabel": "Operating leases" } } }, "localname": "OperatingLeaseLeaseIncome", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLeaseIncomeTableTextBlock": { "auth_ref": [ "r155", "r377" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of components of income from operating lease.", "label": "Operating Lease, Lease Income [Table Text Block]", "terseLabel": "Lease Revenue" } } }, "localname": "OperatingLeaseLeaseIncomeTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_OperatingLeaseLiability": { "auth_ref": [ "r356" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease.", "label": "Operating Lease, Liability", "totalLabel": "Total operating lease liabilities" } } }, "localname": "OperatingLeaseLiability", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLiabilityCurrent": { "auth_ref": [ "r356" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 8.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 1.0, "parentTag": "us-gaap_OperatingLeaseLiability", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.", "label": "Operating Lease, Liability, Current", "terseLabel": "Operating lease liabilities", "verboseLabel": "Operating lease liabilities current liabilities" } } }, "localname": "OperatingLeaseLiabilityCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLiabilityNoncurrent": { "auth_ref": [ "r356" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 5.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails": { "order": 2.0, "parentTag": "us-gaap_OperatingLeaseLiability", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.", "label": "Operating Lease, Liability, Noncurrent", "terseLabel": "Operating lease liabilities", "verboseLabel": "Operating lease liabilities noncurrent liabilities" } } }, "localname": "OperatingLeaseLiabilityNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasePayments": { "auth_ref": [ "r359", "r365" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.", "label": "Operating Lease, Payments", "terseLabel": "Operating cash flows from operating leases" } } }, "localname": "OperatingLeasePayments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseRightOfUseAsset": { "auth_ref": [ "r355" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 6.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's right to use underlying asset under operating lease.", "label": "Operating Lease, Right-of-Use Asset", "terseLabel": "Operating lease right of use asset", "verboseLabel": "Operating lease right of use asset" } } }, "localname": "OperatingLeaseRightOfUseAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent": { "auth_ref": [ "r368", "r371" ], "lang": { "en-US": { "role": { "documentation": "Weighted average discount rate for operating lease calculated at point in time.", "label": "Operating Lease, Weighted Average Discount Rate, Percent", "terseLabel": "Operating Lease, Weighted Average Discount Rate, Percent" } } }, "localname": "OperatingLeaseWeightedAverageDiscountRatePercent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "percentItemType" }, "us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1": { "auth_ref": [ "r367", "r371" ], "lang": { "en-US": { "role": { "documentation": "Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Operating Lease, Weighted Average Remaining Lease Term", "terseLabel": "Operating Lease, Weighted Average Remaining Lease Term" } } }, "localname": "OperatingLeaseWeightedAverageRemainingLeaseTerm1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "durationItemType" }, "us-gaap_OperatingSegmentsMember": { "auth_ref": [ "r158", "r165" ], "lang": { "en-US": { "role": { "documentation": "Identifies components of an entity that engage in business activities from which they may earn revenue and incur expenses, including transactions with other components of the same entity.", "label": "Operating Segments [Member]", "terseLabel": "Operating Segments [Member]" } } }, "localname": "OperatingSegmentsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Organization, Consolidation and Presentation of Financial Statements [Abstract]" } } }, "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock": { "auth_ref": [ "r28", "r318" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.", "label": "Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]", "terseLabel": "Organization and Principles of Consolidation" } } }, "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/OrganizationAndPrinciplesOfConsolidation" ], "xbrltype": "textBlockItemType" }, "us-gaap_OtherAssetsCurrent": { "auth_ref": [ "r77" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 10.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of current assets classified as other.", "label": "Other Assets, Current", "terseLabel": "Other current assets" } } }, "localname": "OtherAssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherAssetsNoncurrent": { "auth_ref": [ "r64" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 9.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of noncurrent assets classified as other.", "label": "Other Assets, Noncurrent", "terseLabel": "Other non-current assets" } } }, "localname": "OtherAssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherCommitmentsAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by type of other commitment.", "label": "Other Commitments [Axis]", "terseLabel": "Other Commitments [Axis]" } } }, "localname": "OtherCommitmentsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "stringItemType" }, "us-gaap_OtherCommitmentsDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other future obligation.", "label": "Other Commitments [Domain]", "terseLabel": "Other Commitments [Domain]" } } }, "localname": "OtherCommitmentsDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "domainItemType" }, "us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent": { "auth_ref": [ "r311", "r312", "r313" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails": { "order": 2.0, "parentTag": "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.", "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Attributable to Parent", "negatedTerseLabel": "Tax (benefit) expense" } } }, "localname": "OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax": { "auth_ref": [ "r85" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.", "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax", "terseLabel": "Amortization of non-qualified employee benefit plan liability, tax" } } }, "localname": "OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Other Comprehensive Income (Loss), Net of Tax [Abstract]", "terseLabel": "Other comprehensive income:" } } }, "localname": "OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "stringItemType" }, "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax": { "auth_ref": [ "r82", "r84" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails": { "order": 1.0, "parentTag": "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.", "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax", "totalLabel": "Total reclassifications before tax" } } }, "localname": "OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax": { "auth_ref": [ "r82", "r84" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.", "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax", "totalLabel": "Total reclassifications for the period" } } }, "localname": "OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax": { "auth_ref": [ "r84", "r88", "r89", "r255" ], "calculation": { "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails": { "order": 1.0, "parentTag": "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.", "label": "Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax", "terseLabel": "Amortization of actuarial losses" } } }, "localname": "OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsAmountsRecognizedInAccumulatedOtherComprehensiveLossDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax": { "auth_ref": [ "r84", "r88", "r89", "r255" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 2.0, "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan.", "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax", "terseLabel": "Amortization of non-qualified employee benefit plan liability, net of taxes" } } }, "localname": "OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherCostAndExpenseOperating": { "auth_ref": [ "r108" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 6.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.", "label": "Other Cost and Expense, Operating", "terseLabel": "Other operating expenses" } } }, "localname": "OtherCostAndExpenseOperating", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherIncreaseDecreaseInEnvironmentalLiabilities": { "auth_ref": [ "r127" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 7.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Other increase (decrease) not attributable to current expense nor cash payments during an accounting period in estimated obligations recorded for probable future costs attributable to environmental contamination issues.", "label": "Other Increase (Decrease) in Environmental Liabilities", "netLabel": "Deferred environmental expenditures, net" } } }, "localname": "OtherIncreaseDecreaseInEnvironmentalLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherLiabilitiesCurrent": { "auth_ref": [ "r32", "r33", "r68" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 9.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.", "label": "Other Liabilities, Current", "terseLabel": "Other current liabilities" } } }, "localname": "OtherLiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherLiabilitiesNoncurrent": { "auth_ref": [ "r72" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 6.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.", "label": "Other Liabilities, Noncurrent", "verboseLabel": "Other non-current liabilities" } } }, "localname": "OtherLiabilitiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherLongTermInvestments": { "auth_ref": [ "r60", "r417" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 5.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of long-term investments classified as other.", "label": "Other Long-term Investments", "terseLabel": "Other investments" } } }, "localname": "OtherLongTermInvestments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherNoncashIncomeExpense": { "auth_ref": [ "r129" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 11.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of income (expense) included in net income that results in no cash inflow (outflow), classified as other.", "label": "Other Noncash Income (Expense)", "negatedTerseLabel": "Other" } } }, "localname": "OtherNoncashIncomeExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherNonoperatingIncomeExpense": { "auth_ref": [ "r109" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of income (expense) related to nonoperating activities, classified as other.", "label": "Other Nonoperating Income (Expense)", "terseLabel": "Other income (expense), net" } } }, "localname": "OtherNonoperatingIncomeExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember": { "auth_ref": [ "r242", "r256", "r257", "r268" ], "lang": { "en-US": { "role": { "documentation": "Plan designed to provide other postretirement benefits. Includes, but is not limited to, defined benefit and defined contribution plans. Excludes pension benefits.", "label": "Other Postretirement Benefits Plan [Member]", "verboseLabel": "Other Postretirement Benefits" } } }, "localname": "OtherPostretirementBenefitPlansDefinedBenefitMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "domainItemType" }, "us-gaap_OtherRegulatoryAssetsLiabilitiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of other costs incurred.", "label": "Other Regulatory Assets (Liabilities) [Member]", "terseLabel": "Other [Member]" } } }, "localname": "OtherRegulatoryAssetsLiabilitiesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_PaymentsForCapitalImprovements": { "auth_ref": [ "r114" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 3.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for acquisition of or capital improvements to properties held for investment (operating, managed, leased) or for use.", "label": "Payments for Capital Improvements", "negatedTerseLabel": "Leasehold improvement expenditures" } } }, "localname": "PaymentsForCapitalImprovements", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsForProceedsFromOtherInvestingActivities": { "auth_ref": [ "r112", "r115", "r140" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 5.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash (inflow) outflow from investing activities classified as other.", "label": "Payments for (Proceeds from) Other Investing Activities", "negatedTerseLabel": "Other" } } }, "localname": "PaymentsForProceedsFromOtherInvestingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsOfDividendsCommonStock": { "auth_ref": [ "r119" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 6.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.", "label": "Payments of Ordinary Dividends, Common Stock", "negatedLabel": "Cash dividend payments on common stock" } } }, "localname": "PaymentsOfDividendsCommonStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired": { "auth_ref": [ "r113" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 2.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.", "label": "Payments to Acquire Businesses, Net of Cash Acquired", "negatedTerseLabel": "Acquisitions, net of cash acquired" } } }, "localname": "PaymentsToAcquireBusinessesNetOfCashAcquired", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquireOilAndGasPropertyAndEquipment": { "auth_ref": [ "r114" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 1.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.", "label": "Payments to Acquire Oil and Gas Property and Equipment", "negatedLabel": "Capital expenditures" } } }, "localname": "PaymentsToAcquireOilAndGasPropertyAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquirePropertyPlantAndEquipment": { "auth_ref": [ "r114" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.", "label": "Payments to Acquire Property, Plant, and Equipment", "terseLabel": "Capital expenditures" } } }, "localname": "PaymentsToAcquirePropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionAndOtherPostretirementBenefitContributions": { "auth_ref": [ "r125" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree.", "label": "Payment for Pension and Other Postretirement Benefits", "terseLabel": "Defined benefit pension plan cash contributions" } } }, "localname": "PensionAndOtherPostretirementBenefitContributions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNarrativeDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionAndOtherPostretirementBenefitExpenseAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]" } } }, "localname": "PensionAndOtherPostretirementBenefitExpenseAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock": { "auth_ref": [ "r269" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for pension and other postretirement benefits.", "label": "Pension and Other Postretirement Benefits Disclosure [Text Block]", "terseLabel": "Pension and Other Postretirement Benefit Costs" } } }, "localname": "PensionAndOtherPostretirementBenefitsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCosts" ], "xbrltype": "textBlockItemType" }, "us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent": { "auth_ref": [ "r50", "r243", "r244", "r247" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.", "label": "Liability, Defined Benefit Plan, Noncurrent", "terseLabel": "Pension and other postretirement benefit liabilities" } } }, "localname": "PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionAndOtherPostretirementPlansCostsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of pension and other postretirement costs.", "label": "Pension and Other Postretirement Plans Costs [Member]", "terseLabel": "Pension and other postretirement benefit liabilities [Member]" } } }, "localname": "PensionAndOtherPostretirementPlansCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_PensionContributions": { "auth_ref": [ "r125" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 6.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.", "label": "Payment for Pension Benefits", "negatedLabel": "Contributions to qualified defined benefit pension plans" } } }, "localname": "PensionContributions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionCostsMember": { "auth_ref": [ "r439" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of pension costs.", "label": "Pension Costs [Member]", "verboseLabel": "Pension balancing [Member]" } } }, "localname": "PensionCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_PensionExpense": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 5.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.", "label": "Pension Cost (Reversal of Cost)", "terseLabel": "Qualified defined benefit pension plan expense" } } }, "localname": "PensionExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionExpenseReversalOfExpenseNoncash": { "auth_ref": [ "r128" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 10.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.", "label": "Pension Expense (Reversal of Expense), Noncash", "terseLabel": "Regulatory disallowance of pension costs" } } }, "localname": "PensionExpenseReversalOfExpenseNoncash", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PensionPlansDefinedBenefitMember": { "auth_ref": [ "r241", "r256", "r257", "r268" ], "lang": { "en-US": { "role": { "documentation": "Plan designed to provide participant with pension benefits. Includes, but is not limited to, defined benefit and defined contribution plans. Excludes other postretirement benefits.", "label": "Pension Plan [Member]", "terseLabel": "Pension Benefits" } } }, "localname": "PensionPlansDefinedBenefitMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "domainItemType" }, "us-gaap_PerformanceSharesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share-based payment arrangement awarded for meeting performance target.", "label": "Performance Shares [Member]", "terseLabel": "Performance Shares" } } }, "localname": "PerformanceSharesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_PlanNameAxis": { "auth_ref": [ "r273", "r282" ], "lang": { "en-US": { "role": { "documentation": "Information by plan name for share-based payment arrangement.", "label": "Plan Name [Axis]", "terseLabel": "Plan Name [Axis]" } } }, "localname": "PlanNameAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_PlanNameDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Plan name for share-based payment arrangement.", "label": "Plan Name [Domain]", "terseLabel": "Plan Name [Domain]" } } }, "localname": "PlanNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_ProceedsFromContributionsFromParent": { "auth_ref": [ "r118" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 1.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from parent as a source of financing that is recorded as additional paid in capital.", "label": "Proceeds from Contributions from Parent", "terseLabel": "Proceeds from Contributions from Parent" } } }, "localname": "ProceedsFromContributionsFromParent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromDivestitureOfBusinesses": { "auth_ref": [ "r110" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.", "label": "Proceeds from Divestiture of Businesses", "terseLabel": "Proceeds from divestiture of businesses" } } }, "localname": "ProceedsFromDivestitureOfBusinesses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfCommonStock": { "auth_ref": [ "r116" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 9.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from the additional capital contribution to the entity.", "label": "Proceeds from Issuance of Common Stock", "terseLabel": "Proceeds from common stock issued" } } }, "localname": "ProceedsFromIssuanceOfCommonStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfDebt": { "auth_ref": [ "r117" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.", "label": "Proceeds from Issuance of Debt", "terseLabel": "Proceeds from Issuance of Debt" } } }, "localname": "ProceedsFromIssuanceOfDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfLongTermDebt": { "auth_ref": [ "r117" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 2.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.", "label": "Proceeds from Issuance of Long-term Debt", "terseLabel": "Long-term debt issued" } } }, "localname": "ProceedsFromIssuanceOfLongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromPaymentsForOtherFinancingActivities": { "auth_ref": [ "r118", "r121", "r140" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 7.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow (outflow) from financing activities classified as other.", "label": "Proceeds from (Payments for) Other Financing Activities", "terseLabel": "Other" } } }, "localname": "ProceedsFromPaymentsForOtherFinancingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromRepaymentsOfLinesOfCredit": { "auth_ref": [ "r140" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 5.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The net cash inflow or cash outflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).", "label": "Proceeds from (Repayments of) Lines of Credit", "terseLabel": "Change in short-term debt" } } }, "localname": "ProceedsFromRepaymentsOfLinesOfCredit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromSaleOfEquityMethodInvestments": { "auth_ref": [ "r110" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.", "label": "Proceeds from Sale of Equity Method Investments", "terseLabel": "Proceeds from Sale of Equity Method Investments" } } }, "localname": "ProceedsFromSaleOfEquityMethodInvestments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromSaleOfLandHeldForUse": { "auth_ref": [ "r111" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 4.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from the sale of land held for use; excludes sales of land held as inventory or investments.", "label": "Proceeds from Sale of Land Held-for-use", "terseLabel": "Proceeds from the sale of assets" } } }, "localname": "ProceedsFromSaleOfLandHeldForUse", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromShortTermDebt": { "auth_ref": [ "r117" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 4.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.", "label": "Proceeds from Short-term Debt", "terseLabel": "Proceeds from term loan due within one year" } } }, "localname": "ProceedsFromShortTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromStockOptionsExercised": { "auth_ref": [ "r116", "r283" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 8.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow from exercise of option under share-based payment arrangement.", "label": "Proceeds from Stock Options Exercised", "terseLabel": "Proceeds from stock options exercised" } } }, "localname": "ProceedsFromStockOptionsExercised", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PropertyPlantAndEquipmentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Property, Plant and Equipment [Abstract]" } } }, "localname": "PropertyPlantAndEquipmentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock": { "auth_ref": [ "r207" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures.", "label": "Property, Plant and Equipment Disclosure [Text Block]", "terseLabel": "Property, Plant and Equipment Disclosure [Text Block]" } } }, "localname": "PropertyPlantAndEquipmentDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentNotes" ], "xbrltype": "textBlockItemType" }, "us-gaap_PropertyPlantAndEquipmentGross": { "auth_ref": [ "r62", "r198" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_PropertyPlantAndEquipmentNet", "weight": 1.0 }, "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails": { "order": 1.0, "parentTag": "us-gaap_PropertyPlantAndEquipmentNet", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.", "label": "Property, Plant and Equipment, Gross", "terseLabel": "Property, plant, and equipment" } } }, "localname": "PropertyPlantAndEquipmentGross", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_PropertyPlantAndEquipmentLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Property, Plant and Equipment [Line Items]", "terseLabel": "Property, Plant and Equipment [Line Items]" } } }, "localname": "PropertyPlantAndEquipmentLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentNet": { "auth_ref": [ "r39", "r40", "r200", "r415" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.", "label": "Property, Plant and Equipment, Net", "totalLabel": "Property, Plant and Equipment, Net" } } }, "localname": "PropertyPlantAndEquipmentNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_PropertyPlantAndEquipmentTransfersAndChanges": { "auth_ref": [ "r201" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.", "label": "Property, Plant and Equipment, Transfers and Changes", "terseLabel": "Property, Plant and Equipment, Transfers and Changes" } } }, "localname": "PropertyPlantAndEquipmentTransfersAndChanges", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_PublicUtilitiesInventory": { "auth_ref": [ "r58" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 7.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The period end amount for a type of inventory held by the utility in a schedule of inventories.", "label": "Public Utilities, Inventory", "terseLabel": "Inventories" } } }, "localname": "PublicUtilitiesInventory", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_PublicUtilitiesPolicyTextBlock": { "auth_ref": [ "r132", "r432" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of accounting policy for public utilities. Examples include a discussion about the scope criteria and appropriateness for and extent of the application of generally accepted accounting principles related to accounting for the effects of certain types of regulation (may include identification of specific business units). Other examples of the disclosures may include: descriptions of the form and economic effects of regulation (for example, but not limited to, recording of regulatory assets and liabilities to the rate setting process); statement about periodic assessments of periodic assessments of generally accepted accounting principles related to accounting for the effects of certain types of regulation; information regarding amortization of and return on regulatory assets and liabilities, including the remaining amounts and recovery or settlement periods; accounting for changes to recovery estimates; AFUDC, plant abandonment's and plant disallowances.", "label": "Public Utilities, Policy [Policy Text Block]", "terseLabel": "Industry Regulation" } } }, "localname": "PublicUtilitiesPolicyTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails": { "order": 2.0, "parentTag": "us-gaap_PropertyPlantAndEquipmentNet", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Period end amount of construction work in progress in public utility.", "label": "Public Utilities, Property, Plant and Equipment, Construction Work in Progress", "terseLabel": "Public Utilities, Property, Plant and Equipment, Construction Work in Progress" } } }, "localname": "PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RatioOfIndebtednessToNetCapital1": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indebtedness divided by net capital.", "label": "Ratio of Indebtedness to Net Capital", "terseLabel": "Ratio of Indebtedness to Net Capital" } } }, "localname": "RatioOfIndebtednessToNetCapital1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "pureItemType" }, "us-gaap_ReceivableWithImputedInterestDiscount": { "auth_ref": [ "r350" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 2.0, "parentTag": "us-gaap_ReceivableWithImputedInterestNetAmount", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Disclosure of the unamortized amount of the discount on the note or receivable which is deducted from the face amount of the receivable or loan. The discount or premium is the difference between the present value and the face amount.", "label": "Receivable with Imputed Interest, Discount", "terseLabel": "Less: imputed interest" } } }, "localname": "ReceivableWithImputedInterestDiscount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ReceivableWithImputedInterestNetAmount": { "auth_ref": [ "r350" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The receivable or note face amount less the unamortized discount or premium.", "label": "Receivable with Imputed Interest, Net Amount", "totalLabel": "Total leases receivable" } } }, "localname": "ReceivableWithImputedInterestNetAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatedOperatingRevenue": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 1.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The total amount of regulated operating revenues recognized during the period.", "label": "Regulated Operating Revenue", "terseLabel": "Natural Gas Distribution revenues" } } }, "localname": "RegulatedOperatingRevenue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatedOperatingRevenueOther": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 2.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount of regulated other operating revenues recognized during the period.", "label": "Regulated Operating Revenue, Other", "terseLabel": "Other regulated services" } } }, "localname": "RegulatedOperatingRevenueOther", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatoryAssetAxis": { "auth_ref": [ "r435", "r436", "r439" ], "lang": { "en-US": { "role": { "documentation": "Information by type of regulatory asset.", "label": "Regulatory Asset [Axis]", "terseLabel": "Regulatory Asset [Axis]" } } }, "localname": "RegulatoryAssetAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RegulatoryAssetDomain": { "auth_ref": [ "r435" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization of costs incurred.", "label": "Regulatory Asset [Domain]", "terseLabel": "Regulatory Asset [Domain]" } } }, "localname": "RegulatoryAssetDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails", "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RegulatoryAssetLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Regulatory Assets [Line Items]", "terseLabel": "Regulatory Assets [Line Items]" } } }, "localname": "RegulatoryAssetLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RegulatoryAssets": { "auth_ref": [ "r435" ], "calculation": { "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetailsCalc2": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.", "label": "Regulatory Assets", "totalLabel": "Regulatory Assets" } } }, "localname": "RegulatoryAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatoryAssetsCurrent": { "auth_ref": [ "r435" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 5.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetailsCalc2": { "order": 1.0, "parentTag": "us-gaap_RegulatoryAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.", "label": "Regulatory Assets, Current", "terseLabel": "Regulatory Assets, Current", "verboseLabel": "Regulatory assets" } } }, "localname": "RegulatoryAssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatoryAssetsNoncurrent": { "auth_ref": [ "r435" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_AssetsNoncurrent", "weight": 1.0 }, "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetailsCalc2": { "order": 2.0, "parentTag": "us-gaap_RegulatoryAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.", "label": "Regulatory Assets, Noncurrent", "netLabel": "Regulatory assets", "terseLabel": "Regulatory Assets, Noncurrent" } } }, "localname": "RegulatoryAssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails", "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatoryLiabilitiesLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Regulatory Liabilities [Line Items]", "terseLabel": "Regulatory Liabilities [Line Items]" } } }, "localname": "RegulatoryLiabilitiesLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RegulatoryLiabilityAxis": { "auth_ref": [ "r437" ], "lang": { "en-US": { "role": { "documentation": "Information by type of regulatory liability.", "label": "Regulatory Liability [Axis]", "terseLabel": "Regulatory Liability [Axis]" } } }, "localname": "RegulatoryLiabilityAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RegulatoryLiabilityCurrent": { "auth_ref": [ "r437" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 6.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.", "label": "Regulatory Liability, Current", "terseLabel": "Regulatory liabilities", "verboseLabel": "Regulatory Liability, Current" } } }, "localname": "RegulatoryLiabilityCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RegulatoryLiabilityDomain": { "auth_ref": [ "r437" ], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in accrual of costs or expenses.", "label": "Regulatory Liability [Domain]", "terseLabel": "Regulatory Liability [Domain]" } } }, "localname": "RegulatoryLiabilityDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RegulatoryLiabilityNoncurrent": { "auth_ref": [ "r72" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.", "label": "Regulatory Liability, Noncurrent", "terseLabel": "Regulatory liabilities", "verboseLabel": "Regulatory Liability, Noncurrent" } } }, "localname": "RegulatoryLiabilityNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RemovalCostsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Rate action of a regulator resulting in capitalization or accrual of removal costs.", "label": "Removal Costs [Member]", "verboseLabel": "Accrued asset removal costs [Member]" } } }, "localname": "RemovalCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RepaymentsOfDebt": { "auth_ref": [ "r120" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.", "label": "Repayments of Debt", "terseLabel": "Repayments of Debt" } } }, "localname": "RepaymentsOfDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RepaymentsOfLongTermDebt": { "auth_ref": [ "r120" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows": { "order": 3.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.", "label": "Repayments of Long-term Debt", "negatedTerseLabel": "Long-term debt retired" } } }, "localname": "RepaymentsOfLongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ResidualValueOfLeasedAsset": { "auth_ref": [ "r378" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of residual asset covered by residual value guarantee. Excludes guarantee considered to be lease payments for lessor.", "label": "Residual Value of Leased Asset", "terseLabel": "Residual Value of Leased Asset" } } }, "localname": "ResidualValueOfLeasedAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RestrictedStockUnitsRSUMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share instrument which is convertible to stock or an equivalent amount of cash, after a specified period of time or when specified performance conditions are met.", "label": "Restricted Stock Units (RSUs) [Member]", "terseLabel": "Restricted Stock Units (RSUs)" } } }, "localname": "RestrictedStockUnitsRSUMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RetainedEarningsAccumulatedDeficit": { "auth_ref": [ "r53", "r231", "r413" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 2.0, "parentTag": "us-gaap_StockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cumulative amount of the reporting entity's undistributed earnings or deficit.", "label": "Retained Earnings (Accumulated Deficit)", "terseLabel": "Retained earnings" } } }, "localname": "RetainedEarningsAccumulatedDeficit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_RetainedEarningsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The cumulative amount of the reporting entity's undistributed earnings or deficit.", "label": "Retained Earnings [Member]", "terseLabel": "Retained Earnings [Member]" } } }, "localname": "RetainedEarningsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_RetirementPlanTypeAxis": { "auth_ref": [ "r241", "r242", "r256", "r257", "r268" ], "lang": { "en-US": { "role": { "documentation": "Information by type of retirement benefit plan. Includes, but is not limited to, retirement benefit arrangement for defined benefit pension and other postretirement plans, retirement benefit arrangement for defined contribution pension and other postretirement plans, and special and contractual termination benefits payable upon retirement.", "label": "Retirement Plan Type [Axis]", "terseLabel": "Retirement Plan Type [Axis]" } } }, "localname": "RetirementPlanTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RetirementPlanTypeDomain": { "auth_ref": [ "r241", "r242", "r256", "r257", "r268" ], "lang": { "en-US": { "role": { "documentation": "Type of plan designed to provide participants with retirement benefits. Includes, but is not limited to, retirement benefit arrangement for defined benefit pension and other postretirement plans, retirement benefit arrangement for defined contribution pension and other postretirement plans, and special and contractual termination benefits payable upon retirement.", "label": "Retirement Plan Type [Domain]", "terseLabel": "Retirement Plan Type [Domain]" } } }, "localname": "RetirementPlanTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsNetPeriodicBenefitCostDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RevenueFromContractWithCustomerAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Revenue from Contract with Customer [Abstract]" } } }, "localname": "RevenueFromContractWithCustomerAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax": { "auth_ref": [ "r234", "r235" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.", "label": "Revenue from Contract with Customer, Excluding Assessed Tax", "terseLabel": "Revenue from Contract with Customer, Excluding Assessed Tax" } } }, "localname": "RevenueFromContractWithCustomerExcludingAssessedTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax": { "auth_ref": [ "r234", "r235" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.", "label": "Revenue from Contract with Customer, Including Assessed Tax", "terseLabel": "Revenue from Contract with Customer, Including Assessed Tax" } } }, "localname": "RevenueFromContractWithCustomerIncludingAssessedTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RevenueFromContractWithCustomerTextBlock": { "auth_ref": [ "r240" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.", "label": "Revenue from Contract with Customer [Text Block]", "terseLabel": "Revenue from Contract with Customer" } } }, "localname": "RevenueFromContractWithCustomerTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueNotes" ], "xbrltype": "textBlockItemType" }, "us-gaap_RevenueRemainingPerformanceObligation": { "auth_ref": [ "r232" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of transaction price allocated to performance obligation that has not been recognized as revenue.", "label": "Revenue, Remaining Performance Obligation, Amount", "terseLabel": "Revenue, Remaining Performance Obligation, Amount" } } }, "localname": "RevenueRemainingPerformanceObligation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]", "terseLabel": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]" } } }, "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1": { "auth_ref": [ "r233" ], "lang": { "en-US": { "role": { "documentation": "Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period", "terseLabel": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Year" } } }, "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "durationItemType" }, "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis": { "auth_ref": [ "r233" ], "lang": { "en-US": { "role": { "documentation": "Start date of time band for expected timing of satisfaction of remaining performance obligation, in CCYY-MM-DD format.", "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]", "terseLabel": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]" } } }, "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about expected timing for satisfying remaining performance obligation.", "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]", "terseLabel": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]" } } }, "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueRevenueRemainingPerformanceObligationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_Revenues": { "auth_ref": [ "r98", "r157", "r158", "r164" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_OperatingIncomeLoss", "weight": 1.0 }, "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 1.0, "parentTag": "us-gaap_GrossProfit", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).", "label": "Revenues", "terseLabel": "Operating revenues", "totalLabel": "Operating revenues", "verboseLabel": "Revenues" } } }, "localname": "Revenues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RevenuesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Revenues [Abstract]", "terseLabel": "Operating revenues [Abstract]" } } }, "localname": "RevenuesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "stringItemType" }, "us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability": { "auth_ref": [ "r366", "r371" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase in right-of-use asset obtained in exchange for finance lease liability.", "label": "Right-of-Use Asset Obtained in Exchange for Finance Lease Liability", "terseLabel": "Right-of-Use Asset Obtained in Exchange for Finance Lease Liability" } } }, "localname": "RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability": { "auth_ref": [ "r366", "r371" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase in right-of-use asset obtained in exchange for operating lease liability.", "label": "Right-of-Use Asset Obtained in Exchange for Operating Lease Liability", "terseLabel": "Operating leases" } } }, "localname": "RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesMember": { "auth_ref": [ "r334" ], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing revenue from sale of goods and services rendered in the normal course of business.", "label": "Sales [Member]", "terseLabel": "Sales [Member]" } } }, "localname": "SalesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/UnrealizedAndRealizedGainLossDetails" ], "xbrltype": "domainItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 1.0, "parentTag": "us-gaap_ReceivableWithImputedInterestNetAmount", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received", "totalLabel": "Total lease revenue" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 5.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Five Years", "terseLabel": "Sales-type Lease, Payments to be Received, Five Years" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 4.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Four Years", "terseLabel": "Sales-type Lease, Payments to be Received, Four Years" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedRemainderOfFiscalYear": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 1.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in remainder of the fiscal year following latest fiscal year. Excludes interim and annual period when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Remainder of Fiscal Year", "terseLabel": "Sales-type Lease, Payments to be Received, Remainder of Fiscal Year" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 6.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases after fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Thereafter", "terseLabel": "Sales-type Lease, Payments to be Received, Thereafter" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 3.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in third fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Three Years", "terseLabel": "Sales-type Lease, Payments to be Received, Three Years" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears": { "auth_ref": [ "r373" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 2.0, "parentTag": "us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in second fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.", "label": "Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Two Years", "terseLabel": "Sales-type Lease, Payments to be Received, Two Years" } } }, "localname": "SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SalesTypeLeaseLeaseIncome": { "auth_ref": [ "r155", "r372", "r377" ], "calculation": { "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails": { "order": 2.0, "parentTag": "us-gaap_LeaseIncome", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lease income from variable lease payments, interest income from net investment on sales-type lease, and profit (loss) recognized at commencement.", "label": "Sales-type Lease, Lease Income", "terseLabel": "Sales-type leases" } } }, "localname": "SalesTypeLeaseLeaseIncome", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock": { "auth_ref": [ "r255" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period for pension plans and/or other employee benefit plans, and reclassification adjustments of other comprehensive income (loss) for the period, as those amounts, including amortization of the net transition asset or obligation, are recognized as components of net periodic benefit cost.", "label": "Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]", "terseLabel": "Schedule of Amounts Recognized in Other Comprehensive Income (Loss)" } } }, "localname": "ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable": { "auth_ref": [ "r297", "r298" ], "lang": { "en-US": { "role": { "documentation": "Schedule reflecting each material business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities.", "label": "Schedule of Business Acquisitions, by Acquisition [Table]", "terseLabel": "Schedule of Business Acquisitions, by Acquisition [Table]" } } }, "localname": "ScheduleOfBusinessAcquisitionsByAcquisitionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of information pertaining to carrying amount and estimated fair value of short-term and long-term debt instruments or arrangements, including but not limited to, identification of terms, features, and collateral requirements.", "label": "Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block]", "terseLabel": "Schedule of Carrying Values and Estimated Fair Values of Debt Instruments" } } }, "localname": "ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock": { "auth_ref": [ "r326", "r331", "r336" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.", "label": "Derivative Instruments, Gain (Loss) [Table Text Block]", "terseLabel": "Income Statement Presentation of Derivative Instruments" } } }, "localname": "ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock": { "auth_ref": [ "r1", "r11", "r12", "r13", "r14", "r15", "r16", "r21", "r24", "r25", "r26", "r205", "r206" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.", "label": "Disposal Groups, Including Discontinued Operations [Table Text Block]", "terseLabel": "Disposal Groups, Including Discontinued Operations" } } }, "localname": "ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DiscontinuedOperationsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock": { "auth_ref": [ "r152" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations.", "label": "Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]", "terseLabel": "EPS Calculation" } } }, "localname": "ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EarningsPerShareTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock": { "auth_ref": [ "r289" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.", "label": "Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]", "terseLabel": "Schedule of Effective Income Tax Rate Reconciliation" } } }, "localname": "ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock": { "auth_ref": [ "r209", "r211", "r213", "r214", "r220" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of environmental loss contingencies by individual site. Does not include loss contingencies that are not environmental in nature.", "label": "Schedule of Environmental Loss Contingencies by Site [Table Text Block]", "terseLabel": "Schedule of Environmental Loss Contingencies by Site" } } }, "localname": "ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEquityMethodInvestmentsLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Schedule of Equity Method Investments [Line Items]", "terseLabel": "Schedule of Equity Method Investments [Line Items]" } } }, "localname": "ScheduleOfEquityMethodInvestmentsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfEquityMethodInvestmentsTable": { "auth_ref": [ "r179" ], "lang": { "en-US": { "role": { "documentation": "Summarization of information required and determined to be disclosed concerning equity method investments in common stock. The summarized information includes: (a) the name of each investee or group of investees for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available.", "label": "Schedule of Equity Method Investments [Table]", "terseLabel": "Schedule of Equity Method Investments [Table]" } } }, "localname": "ScheduleOfEquityMethodInvestmentsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfNetBenefitCostsTableTextBlock": { "auth_ref": [ "r249" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.", "label": "Schedule of Net Benefit Costs [Table Text Block]", "terseLabel": "Schedule of Net Benefit Costs" } } }, "localname": "ScheduleOfNetBenefitCostsTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PensionAndOtherPostretirementBenefitCostsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock": { "auth_ref": [ "r320" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the notional amounts of outstanding derivative positions.", "label": "Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]", "terseLabel": "Schedule of Notional Amounts of Outstanding Derivative Positions" } } }, "localname": "ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfPropertyPlantAndEquipmentTable": { "auth_ref": [ "r63", "r200" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.", "label": "Property, Plant and Equipment [Table]", "terseLabel": "Property, Plant and Equipment [Table]" } } }, "localname": "ScheduleOfPropertyPlantAndEquipmentTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfPublicUtilityPropertyPlantAndEquipmentTextBlock": { "auth_ref": [ "r61", "r433" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of public utility physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, deprecation expense and method used, including composite depreciation, and accumulated deprecation.", "label": "Public Utility Property, Plant, and Equipment [Table Text Block]", "terseLabel": "Public Utility Property, Plant, and Equipment [Table Text Block]" } } }, "localname": "ScheduleOfPublicUtilityPropertyPlantAndEquipmentTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/PropertyPlantAndEquipmentTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock": { "auth_ref": [ "r301" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree.", "label": "Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]", "terseLabel": "Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]" } } }, "localname": "ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/BusinessCombinationsBusinessCombinationsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfRegulatoryAssetsTable": { "auth_ref": [ "r435", "r436", "r439" ], "lang": { "en-US": { "role": { "documentation": "A table of assets that are created when regulatory agencies permit public utilities to defer certain costs that are included in rate-setting to the balance sheet.", "label": "Schedule of Regulatory Assets [Table]", "terseLabel": "Schedule of Regulatory Assets [Table]" } } }, "localname": "ScheduleOfRegulatoryAssetsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryAssetDisclosureDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfRegulatoryAssetsTextBlock": { "auth_ref": [ "r435", "r436", "r439" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of assets that are created when regulatory agencies permit public utilities to defer certain costs included in rate-setting to the balance sheet.", "label": "Schedule of Regulatory Assets [Table Text Block]", "terseLabel": "Schedule of Regulatory Assets" } } }, "localname": "ScheduleOfRegulatoryAssetsTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfRegulatoryLiabilitiesTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "A table of liabilities that are created when regulatory agencies permit public utilities to defer recognition of certain revenues included in rate-setting.", "label": "Schedule of Regulatory Liabilities [Table]", "terseLabel": "Schedule of Regulatory Liabilities [Table]" } } }, "localname": "ScheduleOfRegulatoryLiabilitiesTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/IncomeTaxDetails", "http://www.nwnatural.com/role/SignificantAccountingPoliciesRegulatoryLiabilityDisclosureDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfRegulatoryLiabilitiesTextBlock": { "auth_ref": [ "r437" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of regulatory liabilities. Detailed information about liabilities that result from rate actions of a regulator. Rate actions of a regulator can impose a liability on a regulated enterprise resulting in a regulatory liability.", "label": "Schedule of Regulatory Liabilities [Table Text Block]", "terseLabel": "Schedule of Regulatory Liabilities" } } }, "localname": "ScheduleOfRegulatoryLiabilitiesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPoliciesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable": { "auth_ref": [ "r156", "r161", "r162", "r163", "r193" ], "lang": { "en-US": { "role": { "documentation": "A table disclosing the profit or loss and total assets for each reportable segment of the entity. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.", "label": "Schedule of Segment Reporting Information, by Segment [Table]", "terseLabel": "Schedule of Segment Reporting Information, by Segment [Table]" } } }, "localname": "ScheduleOfSegmentReportingInformationBySegmentTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock": { "auth_ref": [ "r156", "r161", "r162", "r163", "r193" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.", "label": "Schedule of Segment Reporting Information, by Segment [Table Text Block]", "terseLabel": "Schedule of Segment Reporting Information, by Segment" } } }, "localname": "ScheduleOfSegmentReportingInformationBySegmentTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable": { "auth_ref": [ "r273", "r282" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about share-based payment arrangement.", "label": "Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]", "terseLabel": "Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]" } } }, "localname": "ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfShortTermDebtTable": { "auth_ref": [ "r66" ], "lang": { "en-US": { "role": { "documentation": "A table or schedule providing information pertaining to borrowings under which repayment was required in less than twelve months (or normal operating cycle, if longer) after its issuance. It may include: (1) description of the short-term debt arrangement; (2) identification of the lender or type of lender; (3) repayment terms; (4) weighted average interest rate; (5) carrying amount of funds borrowed under the specified short-term debt arrangement as of the balance sheet date and measures of the maximum and average amount outstanding during the period; (6) description of the refinancing of a short-term obligation when that obligation is excluded from current liabilities in the balance sheet; and (7) amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.", "label": "Schedule of Short-term Debt [Table]", "terseLabel": "Schedule of Short-term Debt [Table]" } } }, "localname": "ScheduleOfShortTermDebtTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_SegmentDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Components of an entity that engage in business activities from which they may earn revenue and incur expenses, including transactions with other components of the same entity.", "label": "Segments [Domain]", "terseLabel": "Segments [Domain]" } } }, "localname": "SegmentDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "domainItemType" }, "us-gaap_SegmentReportingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Segment Reporting [Abstract]" } } }, "localname": "SegmentReportingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_SegmentReportingDisclosureTextBlock": { "auth_ref": [ "r170" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.", "label": "Segment Reporting Disclosure [Text Block]", "terseLabel": "Segment Information" } } }, "localname": "SegmentReportingDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformation" ], "xbrltype": "textBlockItemType" }, "us-gaap_SegmentReportingInformationLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Segment Reporting Information [Line Items]", "terseLabel": "Segment Reporting Information [Line Items]" } } }, "localname": "SegmentReportingInformationLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1": { "auth_ref": [ "r274" ], "lang": { "en-US": { "role": { "documentation": "Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.", "label": "Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period", "terseLabel": "Award vesting period" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "durationItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod": { "auth_ref": [ "r278" ], "lang": { "en-US": { "role": { "documentation": "The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).", "label": "Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period", "terseLabel": "Number of RSUs granted in period (in shares)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue": { "auth_ref": [ "r277" ], "lang": { "en-US": { "role": { "documentation": "Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.", "label": "Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value", "terseLabel": "Weighted-average grant date fair value (in dollars per share)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "perShareItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Share-based Compensation Arrangement by Share-based Payment Award [Line Items]", "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award [Line Items]" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted": { "auth_ref": [ "r276" ], "lang": { "en-US": { "role": { "documentation": "Net number of non-option equity instruments granted to participants.", "label": "Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted", "terseLabel": "Number of shares granted (in shares)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain": { "auth_ref": [ "r270", "r275" ], "lang": { "en-US": { "role": { "documentation": "Award under share-based payment arrangement.", "label": "Award Type [Domain]", "terseLabel": "Award Type [Domain]" } } }, "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/StockBasedCompensationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_ShortTermBorrowings": { "auth_ref": [ "r46", "r395", "r411" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 1.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.", "label": "Short-term Debt", "terseLabel": "Short-term debt" } } }, "localname": "ShortTermBorrowings", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_ShortTermDebtLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Short-term Debt [Line Items]", "terseLabel": "Short-term Debt [Line Items]" } } }, "localname": "ShortTermDebtLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtShortTermDebtDetails" ], "xbrltype": "stringItemType" }, "us-gaap_ShortTermLeaseCost": { "auth_ref": [ "r364", "r371" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of short-term lease cost, excluding expense for lease with term of one month or less.", "label": "Short-term Lease, Cost", "terseLabel": "Short-term Lease, Cost" } } }, "localname": "ShortTermLeaseCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_SignificantAccountingPoliciesTextBlock": { "auth_ref": [ "r141" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for all significant accounting policies of the reporting entity.", "label": "Significant Accounting Policies [Text Block]", "terseLabel": "Significant Accounting Policies" } } }, "localname": "SignificantAccountingPoliciesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SignificantAccountingPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_SiteContingencyLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Site Contingency [Line Items]", "terseLabel": "Site Contingency [Line Items]" } } }, "localname": "SiteContingencyLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_SiteContingencyTable": { "auth_ref": [ "r209", "r211", "r213", "r220" ], "lang": { "en-US": { "role": { "documentation": "Information and financial data about the reasonably possible loss or the recognized and additional reasonably possible loss from an environmental remediation obligation.", "label": "Site Contingency [Table]", "terseLabel": "Site Contingency [Table]" } } }, "localname": "SiteContingencyTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/EnvironmentalMattersDetails", "http://www.nwnatural.com/role/EnvironmentalMattersEnvironmentalSitesDetails", "http://www.nwnatural.com/role/EnvironmentalMattersRegulatoryDeferredAssetsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_StatementBusinessSegmentsAxis": { "auth_ref": [ "r10", "r161", "r193", "r204", "r216", "r217", "r424" ], "lang": { "en-US": { "role": { "documentation": "Information by business segments.", "label": "Segments [Axis]", "terseLabel": "Segments [Axis]" } } }, "localname": "StatementBusinessSegmentsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseExpenseDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails", "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails", "http://www.nwnatural.com/role/SegmentInformationNarrativeDetails", "http://www.nwnatural.com/role/SegmentInformationScheduleOfSummarizedFinancialInformationBySegmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_StatementEquityComponentsAxis": { "auth_ref": [ "r74", "r226" ], "lang": { "en-US": { "role": { "documentation": "Information by component of equity.", "label": "Equity Components [Axis]", "terseLabel": "Equity Components [Axis]" } } }, "localname": "StatementEquityComponentsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "stringItemType" }, "us-gaap_StatementLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Statement [Line Items]", "terseLabel": "Statement [Line Items]" } } }, "localname": "StatementLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals" ], "xbrltype": "stringItemType" }, "us-gaap_StatementOfCashFlowsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement of Cash Flows [Abstract]" } } }, "localname": "StatementOfCashFlowsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementOfFinancialPositionAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement of Financial Position [Abstract]" } } }, "localname": "StatementOfFinancialPositionAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementOfStockholdersEquityAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement of Stockholders' Equity [Abstract]" } } }, "localname": "StatementOfStockholdersEquityAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule reflecting a Statement of Income, Statement of Cash Flows, Statement of Financial Position, Statement of Shareholders' Equity and Other Comprehensive Income, or other statement as needed.", "label": "Statement [Table]", "terseLabel": "Statement [Table]" } } }, "localname": "StatementTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets", "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows", "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncomeParentheticals" ], "xbrltype": "stringItemType" }, "us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan": { "auth_ref": [ "r51", "r52", "r226", "r231" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.", "label": "Stock Issued During Period, Value, Employee Stock Purchase Plan", "terseLabel": "Shares issued pursuant to equity based plans" } } }, "localname": "StockIssuedDuringPeriodValueEmployeeStockPurchasePlan", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation": { "auth_ref": [ "r51", "r52", "r231", "r272", "r279" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).", "label": "Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture", "terseLabel": "Stock-based compensation" } } }, "localname": "StockIssuedDuringPeriodValueShareBasedCompensation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockholdersEquity": { "auth_ref": [ "r52", "r54", "r55", "r174" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 4.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.", "label": "Stockholders' Equity Attributable to Parent", "totalLabel": "Total equity" } } }, "localname": "StockholdersEquity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest": { "auth_ref": [ "r308", "r309", "r317" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.", "label": "Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest", "periodEndLabel": "Ending Balance", "periodStartLabel": "Beginning Balance" } } }, "localname": "StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_SubsequentEventMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Identifies event that occurred after the balance sheet date but before financial statements are issued or available to be issued.", "label": "Subsequent Event [Member]", "terseLabel": "Subsequent Event [Member]" } } }, "localname": "SubsequentEventMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_SubsequentEventTypeAxis": { "auth_ref": [ "r383" ], "lang": { "en-US": { "role": { "documentation": "Information by event that occurred after the balance sheet date but before financial statements are issued or available to be issued.", "label": "Subsequent Event Type [Axis]", "terseLabel": "Subsequent Event Type [Axis]" } } }, "localname": "SubsequentEventTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_SubsequentEventTypeDomain": { "auth_ref": [ "r383" ], "lang": { "en-US": { "role": { "documentation": "Event that occurred after the balance sheet date but before financial statements are issued or available to be issued.", "label": "Subsequent Event Type [Domain]", "terseLabel": "Subsequent Event Type [Domain]" } } }, "localname": "SubsequentEventTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_SupplementalCashFlowInformationAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Supplemental Cash Flow Information [Abstract]", "terseLabel": "Supplemental disclosure of cash flow information:" } } }, "localname": "SupplementalCashFlowInformationAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_TaxesExcludingIncomeAndExciseTaxes": { "auth_ref": [ "r109" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 4.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax.", "label": "Taxes, Miscellaneous", "terseLabel": "General taxes" } } }, "localname": "TaxesExcludingIncomeAndExciseTaxes", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_TimingOfTransferOfGoodOrServiceAxis": { "auth_ref": [ "r239" ], "lang": { "en-US": { "role": { "documentation": "Information by timing of transfer of good or service to customer.", "label": "Timing of Transfer of Good or Service [Axis]", "terseLabel": "Timing of Transfer of Good or Service [Axis]" } } }, "localname": "TimingOfTransferOfGoodOrServiceAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "stringItemType" }, "us-gaap_TimingOfTransferOfGoodOrServiceDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Timing of transfer of good or service to customer. Includes, but is not limited to, at point in time or over time.", "label": "Timing of Transfer of Good or Service [Domain]", "terseLabel": "Timing of Transfer of Good or Service [Domain]" } } }, "localname": "TimingOfTransferOfGoodOrServiceDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "us-gaap_TransferredAtPointInTimeMember": { "auth_ref": [ "r239" ], "lang": { "en-US": { "role": { "documentation": "Contract with customer in which good or service is transferred at point in time.", "label": "Transferred at Point in Time [Member]", "terseLabel": "Transferred at Point in Time [Member]" } } }, "localname": "TransferredAtPointInTimeMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "us-gaap_TransferredOverTimeMember": { "auth_ref": [ "r239" ], "lang": { "en-US": { "role": { "documentation": "Contract with customer in which good or service is transferred over time.", "label": "Transferred over Time [Member]", "terseLabel": "Transferred over Time [Member]" } } }, "localname": "TransferredOverTimeMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/RevenueDisaggregationOfRevenueDetails" ], "xbrltype": "domainItemType" }, "us-gaap_TypeOfAdoptionMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Adoption and early adoption of sources of change to generally accepted accounting principles (GAAP) in the United States. The FASB released the FASB Accounting Standards Codification as the authoritative source of literature effective for interim and annual periods ending after September 15, 2009. As part of the Codification process, the FASB issues Accounting Standards Updates to amend the Codification but otherwise the Accounting Standards Updates are not authoritative in their own right. All previous accounting standards (such as FASB Statements of Financial Accounting Standards, FASB Interpretations, FASB Staff Positions, Emerging Issues Task Force Consensuses, other pronouncements of the FASB or other designated bodies, or other forms of GAAP are considered accounting pronouncements) were superseded upon the adoption of the Codification. For an interim period, references to the superseded standards are included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.", "label": "Type of Adoption [Domain]", "terseLabel": "Type of Adoption [Domain]" } } }, "localname": "TypeOfAdoptionMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementOfShareholdersEquity" ], "xbrltype": "domainItemType" }, "us-gaap_TypeOfArrangementAxis": { "auth_ref": [ "r307" ], "lang": { "en-US": { "role": { "documentation": "Information by collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.", "label": "Collaborative Arrangement and Arrangement Other than Collaborative [Axis]", "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative [Axis]" } } }, "localname": "TypeOfArrangementAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseAssetAndLiabilitiesDetails", "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails", "http://www.nwnatural.com/role/PropertyPlantAndEquipmentDetails" ], "xbrltype": "stringItemType" }, "us-gaap_UnamortizedDebtIssuanceExpense": { "auth_ref": [ "r64" ], "calculation": { "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetailsCalc2": { "order": 2.0, "parentTag": "us-gaap_LongTermDebt", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.", "label": "Unamortized Debt Issuance Expense", "negatedLabel": "Unamortized debt issuance costs", "terseLabel": "Unamortized debt issuance costs" } } }, "localname": "UnamortizedDebtIssuanceExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DebtFairValueOfLongTermDebtDetails", "http://www.nwnatural.com/role/LongTermDebtDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_UnbilledReceivablesCurrent": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedBalanceSheets": { "order": 3.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.", "label": "Unbilled Receivables, Current", "terseLabel": "Accrued unbilled revenue" } } }, "localname": "UnbilledReceivablesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_UnderlyingAssetClassAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by underlying asset class.", "label": "Underlying Asset Class [Axis]", "terseLabel": "Underlying Asset Class [Axis]" } } }, "localname": "UnderlyingAssetClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "stringItemType" }, "us-gaap_UnderlyingAssetClassDomain": { "auth_ref": [ "r339" ], "lang": { "en-US": { "role": { "documentation": "Major types of referenced/underlying asset classes (for example, corporate debt, sovereign debt, and structured finance).", "label": "Underlying Asset Class [Domain]", "terseLabel": "Underlying Asset Class [Domain]" } } }, "localname": "UnderlyingAssetClassDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsNotionalAmountsDetails" ], "xbrltype": "domainItemType" }, "us-gaap_UnrealizedGainLossOnDerivatives": { "auth_ref": [ "r128" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.", "label": "Unrealized Gain (Loss) on Derivatives", "negatedLabel": "Unrealized losses on derivatives" } } }, "localname": "UnrealizedGainLossOnDerivatives", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/DerivativeInstrumentsCreditRatingDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_UtilitiesOperatingExpenseGasAndPetroleumPurchased": { "auth_ref": [ "r107" ], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 1.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 }, "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 2.0, "parentTag": "us-gaap_GrossProfit", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of operating expense for purchased gas and petroleum of regulated operation.", "label": "Utilities Operating Expense, Gas and Petroleum Purchased", "terseLabel": "Cost of gas" } } }, "localname": "UtilitiesOperatingExpenseGasAndPetroleumPurchased", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses": { "auth_ref": [], "calculation": { "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome": { "order": 8.0, "parentTag": "us-gaap_OperatingExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of operating expenses for the period that are associated with the utility's normal revenue producing operation; including selling, general, and administrative expenses, costs incurred for routine plant repairs and maintenance, and operations.", "label": "Utilities Operating Expense, Maintenance, Operations, and Other Costs and Expenses", "verboseLabel": "Operations and maintenance" } } }, "localname": "UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_UtilitiesOperatingExpenseTaxes": { "auth_ref": [ "r107" ], "calculation": { "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails": { "order": 4.0, "parentTag": "us-gaap_GrossProfit", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of operating expense for taxes other than income taxes of regulated operation.", "label": "Utilities Operating Expense, Taxes", "verboseLabel": "Revenue taxes" } } }, "localname": "UtilitiesOperatingExpenseTaxes", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/SegmentInformationAdditionalSegmentInformationDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount": { "auth_ref": [ "r315", "r316" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).", "label": "Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount", "terseLabel": "Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount" } } }, "localname": "VariableInterestEntityEntityMaximumLossExposureAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/InvestmentsDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_VariableLeasePayment": { "auth_ref": [ "r360" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow for variable lease payment excluded from lease liability.", "label": "Variable Lease, Payment", "terseLabel": "Variable Lease, Payment" } } }, "localname": "VariableLeasePayment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/LeasesLeaseRevenueDetails" ], "xbrltype": "monetaryItemType" }, "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding": { "auth_ref": [ "r145", "r150" ], "calculation": { "http://www.nwnatural.com/role/EarningsPerShareDetails": { "order": null, "parentTag": null, "root": true, "weight": null } }, "lang": { "en-US": { "role": { "documentation": "The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.", "label": "Weighted Average Number of Shares Outstanding, Diluted", "terseLabel": "Diluted (in shares)", "totalLabel": "Average common shares outstanding - diluted (in shares)" } } }, "localname": "WeightedAverageNumberOfDilutedSharesOutstanding", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "sharesItemType" }, "us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Weighted Average Number of Shares Outstanding, Diluted [Abstract]", "terseLabel": "Average common shares outstanding:" } } }, "localname": "WeightedAverageNumberOfSharesOutstandingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "stringItemType" }, "us-gaap_WeightedAverageNumberOfSharesOutstandingBasic": { "auth_ref": [ "r144", "r150" ], "calculation": { "http://www.nwnatural.com/role/EarningsPerShareDetails": { "order": 1.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.", "label": "Weighted Average Number of Shares Outstanding, Basic", "terseLabel": "Basic (in shares)", "verboseLabel": "Average common shares outstanding - basic (in shares)" } } }, "localname": "WeightedAverageNumberOfSharesOutstandingBasic", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.nwnatural.com/role/ConsolidatedStatementsOfComprehensiveIncome", "http://www.nwnatural.com/role/EarningsPerShareDetails" ], "xbrltype": "sharesItemType" } }, "unitCount": 7 } }, "std_ref": { "r0": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759" }, "r1": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759" }, "r10": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(d)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760" }, "r100": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(14))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r101": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(20))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r102": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(21))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r103": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(b)(7)(c))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r104": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(b)(9)(a))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r105": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.1,2)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r106": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.13)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r107": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.2(b))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r108": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.3)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r109": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.9)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r11": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760" }, "r110": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585" }, "r111": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585" }, "r112": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585" }, "r113": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585" }, "r114": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585" }, "r115": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585" }, "r116": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585" }, "r117": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585" }, "r118": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585" }, "r119": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585" }, "r12": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=d3e1474-107760" }, "r120": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585" }, "r121": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585" }, "r122": { "Name": "Accounting Standards Codification", "Paragraph": "17", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585" }, "r123": { "Name": "Accounting Standards Codification", "Paragraph": "24", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3521-108585" }, "r124": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(e)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585" }, "r125": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(g)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585" }, "r126": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585" }, "r127": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585" }, "r128": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585" }, "r129": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585" }, "r13": { "Name": "Accounting Standards Codification", "Paragraph": "3A", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721659-107760" }, "r130": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3044-108585" }, "r131": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586" }, "r132": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790" }, "r133": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(h)(2))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r134": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(h))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r135": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(k))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r136": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(e),(f))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r137": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(h)(2))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r138": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(k)(1))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r139": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(n)(2))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r14": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721663-107760" }, "r140": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.12-04(a))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690" }, "r141": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "235", "URI": "http://asc.fasb.org/topic&trid=2122369" }, "r142": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "250", "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794" }, "r143": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "250", "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794" }, "r144": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1448-109256" }, "r145": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1505-109256" }, "r146": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256" }, "r147": { "Name": "Accounting Standards Codification", "Paragraph": "28A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1500-109256" }, "r148": { "Name": "Accounting Standards Codification", "Paragraph": "60B", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256" }, "r149": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256" }, "r15": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721665-107760" }, "r150": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257" }, "r151": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257" }, "r152": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257" }, "r153": { "Name": "Accounting Standards Codification", "Paragraph": "52", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258" }, "r154": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "260", "URI": "http://asc.fasb.org/topic&trid=2144383" }, "r155": { "Name": "Accounting Standards Codification", "Paragraph": "6A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "270", "URI": "http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306" }, "r156": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8721-108599" }, "r157": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r158": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r159": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(e)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r16": { "Name": "Accounting Standards Codification", "Paragraph": "5A", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721671-107760" }, "r160": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(h)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r161": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r162": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599" }, "r163": { "Name": "Accounting Standards Codification", "Paragraph": "30", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8906-108599" }, "r164": { "Name": "Accounting Standards Codification", "Paragraph": "32", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599" }, "r165": { "Name": "Accounting Standards Codification", "Paragraph": "32", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599" }, "r166": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8475-108599" }, "r167": { "Name": "Accounting Standards Codification", "Paragraph": "40", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e9031-108599" }, "r168": { "Name": "Accounting Standards Codification", "Paragraph": "41", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e9038-108599" }, "r169": { "Name": "Accounting Standards Codification", "Paragraph": "42", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e9054-108599" }, "r17": { "Name": "Accounting Standards Codification", "Paragraph": "5B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760" }, "r170": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "280", "URI": "http://asc.fasb.org/topic&trid=2134510" }, "r171": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522" }, "r172": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118952595&loc=d3e4531-111522" }, "r173": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524" }, "r174": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB Topic 4.E)", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707" }, "r175": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "320", "URI": "http://asc.fasb.org/topic&trid=2196928" }, "r176": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "321", "URI": "http://asc.fasb.org/topic&trid=75115024" }, "r177": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(1)", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571" }, "r178": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(3)", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571" }, "r179": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(b)", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571" }, "r18": { "Name": "Accounting Standards Codification", "Paragraph": "5B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760" }, "r180": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "323", "URI": "http://asc.fasb.org/topic&trid=2196965" }, "r181": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "325", "URI": "http://asc.fasb.org/topic&trid=2197064" }, "r182": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446" }, "r183": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447" }, "r184": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(d)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447" }, "r185": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(f)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447" }, "r186": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447" }, "r187": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447" }, "r188": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955255&loc=SL82921835-210448" }, "r189": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266" }, "r19": { "Name": "Accounting Standards Codification", "Paragraph": "5B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)(1)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760" }, "r190": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266" }, "r191": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975" }, "r192": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(e)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267" }, "r193": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267" }, "r194": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267" }, "r195": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226348&loc=d3e2510-110228" }, "r196": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226348&loc=d3e2473-110228" }, "r197": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229" }, "r198": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229" }, "r199": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229" }, "r2": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721494-107759" }, "r20": { "Name": "Accounting Standards Codification", "Paragraph": "5B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(e)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760" }, "r200": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229" }, "r201": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230" }, "r202": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230" }, "r203": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(e)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230" }, "r204": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(f)", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230" }, "r205": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230" }, "r206": { "Name": "Accounting Standards Codification", "Paragraph": "3A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "360", "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=SL51724579-110230" }, "r207": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "360", "URI": "http://asc.fasb.org/topic&trid=2155823" }, "r208": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=109237650&loc=d3e13064-110858" }, "r209": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(d)", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859" }, "r21": { "Name": "Accounting Standards Codification", "Paragraph": "5B", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760" }, "r210": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(d)(1)", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859" }, "r211": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13283-110859" }, "r212": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(a)", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859" }, "r213": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859" }, "r214": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "410", "URI": "http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859" }, "r215": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "30", "Topic": "410", "URI": "http://asc.fasb.org/subtopic&trid=2175709" }, "r216": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "420", "URI": "http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869" }, "r217": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB Topic 5.P.4(d))", "Topic": "420", "URI": "http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747" }, "r218": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "450", "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349" }, "r219": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "450", "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14615-108349" }, "r22": { "Name": "Accounting Standards Codification", "Paragraph": "5C", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(2)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760" }, "r220": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "20", "Subparagraph": "(SAB TOPIC 5.Y.Q2)", "Topic": "450", "URI": "http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751" }, "r221": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "20", "Subparagraph": "(SAB Topic 5.Y.Q4)", "Topic": "450", "URI": "http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751" }, "r222": { "Name": "Accounting Standards Codification", "Paragraph": "12A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "470", "URI": "http://asc.fasb.org/extlink&oid=99376301&loc=SL5988623-112600" }, "r223": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)(1)", "Topic": "470", "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870" }, "r224": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)(3)", "Topic": "470", "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870" }, "r225": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "470", "URI": "http://asc.fasb.org/topic&trid=2208564" }, "r226": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644" }, "r227": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644" }, "r228": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644" }, "r229": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644" }, "r23": { "Name": "Accounting Standards Codification", "Paragraph": "5C", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)(2)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760" }, "r230": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644" }, "r231": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.3-04)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770" }, "r232": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045" }, "r233": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)(1)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045" }, "r234": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045" }, "r235": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045" }, "r236": { "Name": "Accounting Standards Codification", "Paragraph": "91", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046" }, "r237": { "Name": "Accounting Standards Codification", "Paragraph": "91", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046" }, "r238": { "Name": "Accounting Standards Codification", "Paragraph": "91", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046" }, "r239": { "Name": "Accounting Standards Codification", "Paragraph": "91", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(f)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046" }, "r24": { "Name": "Accounting Standards Codification", "Paragraph": "5C", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760" }, "r240": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "606", "URI": "http://asc.fasb.org/topic&trid=49130388" }, "r241": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "15", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "712", "URI": "http://asc.fasb.org/extlink&oid=6410066&loc=d3e79218-111664" }, "r242": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "15", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "712", "URI": "http://asc.fasb.org/extlink&oid=6410066&loc=d3e79218-111664" }, "r243": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=109237824&loc=d3e1703-114919" }, "r244": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=109237824&loc=d3e1731-114919" }, "r245": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(1)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r246": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(2)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r247": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r248": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(d)(ii)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r249": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r25": { "Name": "Accounting Standards Codification", "Paragraph": "5D", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721677-107760" }, "r250": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)(1)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r251": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)(2)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r252": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)(3)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r253": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)(4)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r254": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(h)(5)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r255": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(i)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r256": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r257": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2410-114920" }, "r258": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920" }, "r259": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2439-114920" }, "r26": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760" }, "r260": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r261": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(1)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r262": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(2)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r263": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(3)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r264": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(4)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r265": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(5)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r266": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920" }, "r267": { "Name": "Accounting Standards Codification", "Paragraph": "17", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921" }, "r268": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "70", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942" }, "r269": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "715", "URI": "http://asc.fasb.org/topic&trid=2235017" }, "r27": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/subtopic&trid=2122178" }, "r270": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901" }, "r271": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901" }, "r272": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901" }, "r273": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901" }, "r274": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(1)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r275": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a),(g)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r276": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)(iv)(1)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r277": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(2)(i)-(ii)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r278": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(2)(iii)(1)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r279": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)(1)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r28": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "205", "URI": "http://asc.fasb.org/topic&trid=2122149" }, "r280": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(h)(1)(i)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r281": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(i)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r282": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901" }, "r283": { "Name": "Accounting Standards Codification", "Paragraph": "2A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=SL79508275-113901" }, "r284": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB Topic 14.F)", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809" }, "r285": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "718", "URI": "http://asc.fasb.org/topic&trid=2228938" }, "r286": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=d3e31917-109318" }, "r287": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=d3e31931-109318" }, "r288": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319" }, "r289": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319" }, "r29": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765" }, "r290": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319" }, "r291": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319" }, "r292": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB TOPIC 6.I)", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817" }, "r293": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324" }, "r294": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324" }, "r295": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "740", "URI": "http://asc.fasb.org/topic&trid=2144680" }, "r296": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(h)(1)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463" }, "r297": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463" }, "r298": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1486-128463" }, "r299": { "Name": "Accounting Standards Codification", "Paragraph": "37", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464" }, "r3": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721494-107759" }, "r30": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765" }, "r300": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472" }, "r301": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472" }, "r302": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "30", "SubTopic": "30", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477" }, "r303": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "30", "SubTopic": "30", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477" }, "r304": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479" }, "r305": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(d)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479" }, "r306": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "805", "URI": "http://asc.fasb.org/topic&trid=2303972" }, "r307": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "808", "URI": "http://asc.fasb.org/extlink&oid=6931272&loc=SL5834143-161434" }, "r308": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4568447-111683" }, "r309": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4568740-111683" }, "r31": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6801-107765" }, "r310": { "Name": "Accounting Standards Codification", "Paragraph": "18", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4613673-111683" }, "r311": { "Name": "Accounting Standards Codification", "Paragraph": "19", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683" }, "r312": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4569643-111683" }, "r313": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(3)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r314": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c),(3)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r315": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "b", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685" }, "r316": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685" }, "r317": { "Name": "Accounting Standards Codification", "Paragraph": "4I", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=116874947&loc=SL4590271-111686" }, "r318": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "810", "URI": "http://asc.fasb.org/topic&trid=2197479" }, "r319": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5579240-113959" }, "r32": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6904-107765" }, "r320": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959" }, "r321": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959" }, "r322": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959" }, "r323": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41620-113959" }, "r324": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41638-113959" }, "r325": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r326": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r327": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)(1)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r328": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r329": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r33": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6911-107765" }, "r330": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r331": { "Name": "Accounting Standards Codification", "Paragraph": "4C", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959" }, "r332": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(2)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r333": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(4)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r334": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r335": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r336": { "Name": "Accounting Standards Codification", "Paragraph": "4E", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624181-113959" }, "r337": { "Name": "Accounting Standards Codification", "Paragraph": "4H", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959" }, "r338": { "Name": "Accounting Standards Codification", "Paragraph": "4H", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(e)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959" }, "r339": { "Name": "Accounting Standards Codification", "Paragraph": "4K", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5708775-113959" }, "r34": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6935-107765" }, "r340": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41641-113959" }, "r341": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959" }, "r342": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959" }, "r343": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "25", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986" }, "r344": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "815", "URI": "http://asc.fasb.org/topic&trid=2229140" }, "r345": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r346": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r347": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258" }, "r348": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611" }, "r349": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "230", "Topic": "830", "URI": "http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906" }, "r35": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e7018-107765" }, "r350": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "835", "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399" }, "r351": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "835", "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399" }, "r352": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "55", "SubTopic": "30", "Topic": "835", "URI": "http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400" }, "r353": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(a)", "Topic": "840", "URI": "http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738" }, "r354": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "840", "URI": "http://asc.fasb.org/topic&trid=2208923" }, "r355": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977" }, "r356": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977" }, "r357": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977" }, "r358": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977" }, "r359": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977" }, "r36": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(10))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r360": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Subparagraph": "(d)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977" }, "r361": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)(3)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980" }, "r362": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980" }, "r363": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980" }, "r364": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r365": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(g)(1)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r366": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(g)(2)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r367": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(g)(3)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r368": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(g)(4)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r369": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r37": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(11))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r370": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980" }, "r371": { "Name": "Accounting Standards Codification", "Paragraph": "53", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971" }, "r372": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978" }, "r373": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919391-209981" }, "r374": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981" }, "r375": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(a)(3)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919359-209981" }, "r376": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919359-209981" }, "r377": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981" }, "r378": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=119202524&loc=SL77919381-209981" }, "r379": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864" }, "r38": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(12))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r380": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39599-107864" }, "r381": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864" }, "r382": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "852", "URI": "http://asc.fasb.org/extlink&oid=6918054&loc=d3e56071-112765" }, "r383": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "855", "URI": "http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662" }, "r384": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "855", "URI": "http://asc.fasb.org/extlink&oid=6842918&loc=SL6314020-165662" }, "r385": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447" }, "r386": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447" }, "r387": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61858-109447" }, "r388": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61869-109447" }, "r389": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61872-109447" }, "r39": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(13))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r390": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61884-109447" }, "r391": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "55", "SubTopic": "235", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=34713648&loc=d3e62984-109448" }, "r392": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "25", "SubTopic": "20", "Topic": "940", "URI": "http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953" }, "r393": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(11))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r394": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(13)(2))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r395": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(13))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r396": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(15)(1))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r397": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(16))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r398": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(23))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r399": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03.10)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r4": { "Name": "Accounting Standards Codification", "Paragraph": "1D", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721503-107759" }, "r40": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(14))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r400": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03.17)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r401": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(19))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r402": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04(15))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r403": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04(20))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r404": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04(22))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r405": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04(23))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r406": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "470", "Subparagraph": "(g)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823" }, "r407": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "470", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823" }, "r408": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(16))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r409": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(12))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r41": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(15))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r410": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(15)(b)(1))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r411": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(16)(a)(1))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r412": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(16))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r413": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(23)(a)(4))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r414": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(25))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r415": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(8))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r416": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03.(a),19)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r417": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03.1(f))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r418": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03.5(c))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r419": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(11))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r42": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(16))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r420": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(12))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r421": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(18))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r422": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(19))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r423": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(8))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r424": { "Name": "Accounting Standards Codification", "Paragraph": "4H", "Publisher": "FASB", "Section": "50", "SubTopic": "40", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116884468&loc=SL65671331-158438" }, "r425": { "Name": "Accounting Standards Codification", "Paragraph": "13H", "Publisher": "FASB", "Section": "55", "SubTopic": "40", "Subparagraph": "(a)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=117419784&loc=SL117783719-158441" }, "r426": { "Name": "Accounting Standards Codification", "Paragraph": "13H", "Publisher": "FASB", "Section": "55", "SubTopic": "40", "Subparagraph": "(b)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=117419784&loc=SL117783719-158441" }, "r427": { "Name": "Accounting Standards Codification", "Paragraph": "13H", "Publisher": "FASB", "Section": "55", "SubTopic": "40", "Subparagraph": "(c)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=117419784&loc=SL117783719-158441" }, "r428": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.6-04(12)(b)(3))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996" }, "r429": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "310", "Subparagraph": "(SX 210.12-29(Footnote 4))", "Topic": "948", "URI": "http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014" }, "r43": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(17))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r430": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "360", "Subparagraph": "(SX 210.12-28(Footnote 2))", "Topic": "970", "URI": "http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024" }, "r431": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "360", "Subparagraph": "(SX 210.12-28(Footnote 4))", "Topic": "970", "URI": "http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024" }, "r432": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "05", "SubTopic": "10", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=79984601&loc=d3e39995-110364" }, "r433": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=84167750&loc=d3e42232-110370" }, "r434": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "25", "SubTopic": "340", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=77907324&loc=d3e43603-110378" }, "r435": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "340", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382" }, "r436": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "340", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6499975&loc=d3e44264-110382" }, "r437": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "25", "SubTopic": "405", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394" }, "r438": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "410", "Subparagraph": "(SAB Topic 10.F)", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6228715&loc=d3e660557-123036" }, "r439": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "715", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6501251&loc=d3e52485-110419" }, "r44": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(19)(a)(3))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r440": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "25", "SubTopic": "740", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6501382&loc=d3e54053-110423" }, "r441": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "25", "SubTopic": "740", "Topic": "980", "URI": "http://asc.fasb.org/extlink&oid=6501382&loc=d3e54136-110423" }, "r442": { "Name": "Exchange Act", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "b" }, "r443": { "Name": "Exchange Act", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "d1-1" }, "r444": { "Name": "Form 10-Q", "Number": "240", "Publisher": "SEC", "Section": "13", "Subsection": "a-13" }, "r445": { "Name": "Forms 10-K, 10-Q, 20-F", "Number": "240", "Publisher": "SEC", "Section": "13", "Subsection": "a-1-" }, "r446": { "Name": "Regulation 12B", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "b-2" }, "r447": { "Name": "Regulation S-T", "Number": "232", "Publisher": "SEC", "Section": "405" }, "r45": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(19)(a)(5))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r46": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(19)(a))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r47": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(19))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r48": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(20))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r49": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(22))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r5": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=d3e957-107759" }, "r50": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(24))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r51": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(28))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r52": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(29))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r53": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(30)(a)(3))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r54": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(30))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r55": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(31))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r56": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(32))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r57": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(4)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r58": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(6)(a))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r59": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.1)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r6": { "Name": "Accounting Standards Codification", "Paragraph": "3A", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721523-107759" }, "r60": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.12)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r61": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.13(b))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r62": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.13)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r63": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.14)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r64": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.17)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r65": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.19(a))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r66": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.19)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r67": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.19,20)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r68": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.20)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r69": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.21)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r7": { "Name": "Accounting Standards Codification", "Paragraph": "3B", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=SL51721525-107759" }, "r70": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22(a)(1))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r71": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r72": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.24)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r73": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.25)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r74": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.29-31)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r75": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.3(a)(2))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r76": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.3(a)(4))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r77": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.8)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r78": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.9)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r79": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312" }, "r8": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222160&loc=d3e1012-107759" }, "r80": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313" }, "r81": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=99393222&loc=SL20226006-175313" }, "r82": { "Name": "Accounting Standards Codification", "Paragraph": "10A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(i-k)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580" }, "r83": { "Name": "Accounting Standards Codification", "Paragraph": "10A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580" }, "r84": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580" }, "r85": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580" }, "r86": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580" }, "r87": { "Name": "Accounting Standards Codification", "Paragraph": "14A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580" }, "r88": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e689-108580" }, "r89": { "Name": "Accounting Standards Codification", "Paragraph": "17A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL34724391-108580" }, "r9": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "205", "URI": "http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760" }, "r90": { "Name": "Accounting Standards Codification", "Paragraph": "17B", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL34724394-108580" }, "r91": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580" }, "r92": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580" }, "r93": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580" }, "r94": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580" }, "r95": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e557-108580" }, "r96": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "65", "SubTopic": "10", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116657190&loc=SL116659633-172590" }, "r97": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(13))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868656-224227" }, "r98": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(1))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r99": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(10))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" } }, "version": "2.1" }