2.4.0.82410401 - Disclosure - Other Jefferson County Public Utility District (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$I2013Q2_us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis_psd_JeffersonCountyPublicUtilityDistrictMemberhttp://www.sec.gov/CIK0001085392instant2013-06-30T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse1false USDtruefalse$I2013Q2_us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis_psd_JeffersonCountyPublicUtilityDistrictMemberhttp://www.sec.gov/CIK0001085392instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseJefferson County Public Utility District [Member]us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxisxbrldihttp://xbrl.org/2006/xbrldipsd_JeffersonCountyPublicUtilityDistrictMemberus-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Jefferson County Public Utility District [Member]2true 3us-gaap_SignificantAcquisitionsAndDisposalsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Significant Acquisitions and Disposals [Line Items]3false 4us-gaap_PropertyPlantAndEquipmentGrossus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse4640000046.4USD$falsetruefalsexbrli:monetaryItemTypemonetaryGross amount of long-lived 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, furniture and fixtures, and computer equipment.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false2Property, Plant and Equipment, Net Book Value4false 4us-gaap_SignificantAcquisitionsAndDisposalsGainLossOnSaleOrDisposalPretaxus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse6090000060.9USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe difference between the value of the consideration received by the Entity on the sale or disposal and net book value of assets sold or disposed, before any tax related impact.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 false2Significant Acquisitions and Disposals, Gain (Loss) on Sale or Disposal, PretaxfalseOther Jefferson County Public Utility District (Details) (Jefferson County Public Utility District [Member], USD $)HundredThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.pugetenergy.com/role/OtherJeffersonCountyPublicUtilityDistrictDetails14