Commercial paper, Average remaining maturity

No definition available.

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- Definition

Commercial paper, Maximum remaining maturity

+ References

No definition available.

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- Definition

Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13)(2))
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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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Balance Type:	debit
Period Type:	duration

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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-Name Accounting Standards Codification
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- Definition

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.

+ References

No definition available.

+ Details

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Debt Short-term Debt (Details) $ in Thousands	3 Months Ended
Debt Short-term Debt (Details) $ in Thousands	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)
Short-term Debt [Line Items]
Short-term debt	$ 550,000	$ 149,100	$ 176,391
Commercial paper, Maximum remaining maturity	45 days
Commercial paper, Average remaining maturity	25 days
Ratio of Indebtedness to Net Capital	0.625
Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Short-term debt	$ 450,000	$ 125,100	$ 176,300
Commercial Paper	$ 73,000
Ratio of Indebtedness to Net Capital	0.614
Line of Credit [Member]
Short-term Debt [Line Items]
Short-term debt	$ 100,000
Line of Credit [Member] \| Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Short-term debt	$ 227,000
364-Day Term Loan, Due 2021 [Member]
Short-term Debt [Line Items]
Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio	70.00%
364-Day Term Loan, Due 2021 [Member] \| Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Proceeds from Issuance of Debt	$ 150,000