2.4.0.82406402 - Disclosure - Retirement Benefits Net Periodic Benefit Cost (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDtruefalse$D2013Q2YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDtruefalse$D2012Q4YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDtruefalse$D2013Q2YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDtruefalse$D2012Q4YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5false USDtruefalse$D2013Q2YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6false USDtruefalse$D2012Q4YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$7false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$9false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$10false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$11false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$12false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$13false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$14false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$15false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$16false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$17false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$18false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_ParentCompanyMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalsePUGET ENERGY [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$19false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$20false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$21false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$22false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseQualified Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$23false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$24false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$25false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$26false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_psd_SupplementalExecutiveRetirementPlanMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseSERP Pension Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldipsd_SupplementalExecutiveRetirementPlanMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$27false USDtruefalse$D2013Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$28false USDtruefalse$D2012Q2_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$29false USDtruefalse$D2013Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$30false USDtruefalse$D2012Q2YTD_dei_LegalEntityAxis_us-gaap_SubsidiariesMember_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_OtherPensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-06-30T00:00:00falsefalseSubsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsidiariesMemberdei_LegalEntityAxisexplicitMemberfalsefalseOther Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalse28falsefalsefalse00falsefalsefalse29falsefalsefalse00falsefalsefalse30falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Components of net periodic benefit cost:2false 5us-gaap_DefinedBenefitPlanServiceCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-9642000-9642USD$falsetruefalse2truefalsefalse-16926000-16926USD$falsetruefalse3truefalsefalse-749000-749USD$falsetruefalse4truefalsefalse-1073000-1073USD$falsetruefalse5truefalsefalse-67000-67USD$falsetruefalse6truefalsefalse-139000-139USD$falsetruefalse7truefalsefalse49340004934USD$falsetruefalse8truefalsefalse42290004229USD$falsetruefalse9truefalsefalse96430009643USD$falsetruefalse10truefalsefalse84630008463USD$falsetruefalse11truefalsefalse375000375USD$falsetruefalse12truefalsefalse268000268USD$falsetruefalse13truefalsefalse749000749USD$falsetruefalse14truefalsefalse537000537USD$falsetruefalse15truefalsefalse3200032USD$falsetruefalse16truefalsefalse3200032USD$falsetruefalse17truefalsefalse6700067USD$falsetruefalse18truefalsefalse7000070USD$falsetruefalse19truefalsefalse49340004934USD$falsetruefalse20truefalsefalse42290004229USD$falsetruefalse21truefalsefalse96430009643USD$falsetruefalse22truefalsefalse84630008463USD$falsetruefalse23truefalsefalse375000375USD$falsetruefalse24truefalsefalse268000268USD$falsetruefalse25truefalsefalse749000749USD$falsetruefalse26truefalsefalse537000537USD$falsetruefalse27truefalsefalse3200032USD$falsetruefalse28truefalsefalse3200032USD$falsetruefalse29truefalsefalse6700067USD$falsetruefalse30truefalsefalse7000070USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 -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 Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a, h -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Service cost3false 5us-gaap_DefinedBenefitPlanInterestCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-12377000-12377falsefalsefalse2truefalsefalse-25986000-25986falsefalsefalse3truefalsefalse-1023000-1023falsefalsefalse4truefalsefalse-2152000-2152falsefalsefalse5truefalsefalse-332000-332falsefalsefalse6truefalsefalse-751000-751falsefalsefalse7truefalsefalse61820006182falsefalsefalse8truefalsefalse65510006551falsefalsefalse9truefalsefalse1237700012377falsefalsefalse10truefalsefalse1299300012993falsefalsefalse11truefalsefalse511000511falsefalsefalse12truefalsefalse538000538falsefalsefalse13truefalsefalse10220001022falsefalsefalse14truefalsefalse10760001076falsefalsefalse15truefalsefalse155000155falsefalsefalse16truefalsefalse188000188falsefalsefalse17truefalsefalse332000332falsefalsefalse18truefalsefalse375000375falsefalsefalse19truefalsefalse61820006182falsefalsefalse20truefalsefalse65510006551falsefalsefalse21truefalsefalse1237700012377falsefalsefalse22truefalsefalse1299300012993falsefalsefalse23truefalsefalse511000511falsefalsefalse24truefalsefalse538000538falsefalsefalse25truefalsefalse10220001022falsefalsefalse26truefalsefalse10760001076falsefalsefalse27truefalsefalse155000155falsefalsefalse28truefalsefalse188000188falsefalsefalse29truefalsefalse332000332falsefalsefalse30truefalsefalse375000375falsefalsefalsexbrli:monetaryItemTypemonetaryThe increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 -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 Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a, h -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. false2Interest cost4false 5us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssetsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse-9696000-9696falsefalsefalse8truefalsefalse-9101000-9101falsefalsefalse9truefalsefalse-19548000-19548falsefalsefalse10truefalsefalse-18102000-18102falsefalsefalse11truefalsefalse00falsefalsefalse12truefalsefalse00falsefalsefalse13truefalsefalse00falsefalsefalse14truefalsefalse00falsefalsefalse15truefalsefalse-109000-109falsefalsefalse16truefalsefalse-109000-109falsefalsefalse17truefalsefalse-218000-218falsefalsefalse18truefalsefalse-218000-218falsefalsefalse19truefalsefalse-10094000-10094falsefalsefalse20truefalsefalse-10434000-10434falsefalsefalse21truefalsefalse-20343000-20343falsefalsefalse22truefalsefalse-20767000-20767falsefalsefalse23truefalsefalse00falsefalsefalse24truefalsefalse00falsefalsefalse25truefalsefalse00falsefalsefalse26truefalsefalse00falsefalsefalse27truefalsefalse-109000-109falsefalsefalse28truefalsefalse-109000-109falsefalsefalse29truefalsefalse-218000-218falsefalsefalse30truefalsefalse-218000-218falsefalsefalsexbrli:monetaryItemTypemonetaryAn amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 -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 Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512136 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Expected return on plan assets5false 5us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCreditus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse-495000-495falsefalsefalse8truefalsefalse-495000-495falsefalsefalse9truefalsefalse-990000-990falsefalsefalse10truefalsefalse-990000-990falsefalsefalse11truefalsefalse-4000-4falsefalsefalse12truefalsefalse00falsefalsefalse13truefalsefalse-9000-9falsefalsefalse14truefalsefalse00falsefalsefalse15truefalsefalse00falsefalsefalse16truefalsefalse00falsefalsefalse17truefalsefalse00falsefalsefalse18truefalsefalse00falsefalsefalse19truefalsefalse-393000-393falsefalsefalse20truefalsefalse-393000-393falsefalsefalse21truefalsefalse-787000-787falsefalsefalse22truefalsefalse-787000-787falsefalsefalse23truefalsefalse-4000-4falsefalsefalse24truefalsefalse7400074falsefalsefalse25truefalsefalse-8000-8falsefalsefalse26truefalsefalse146000146falsefalsefalse27truefalsefalse80008falsefalsefalse28truefalsefalse90009falsefalsefalse29truefalsefalse1400014falsefalsefalse30truefalsefalse1800018falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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. false2Amortization of prior service cost6false 5us-gaap_DefinedBenefitPlanAmortizationOfGainsLossesus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse794000794falsefalsefalse8truefalsefalse234000234falsefalsefalse9truefalsefalse14440001444falsefalsefalse10truefalsefalse384000384falsefalsefalse11truefalsefalse365000365falsefalsefalse12truefalsefalse176000176falsefalsefalse13truefalsefalse731000731falsefalsefalse14truefalsefalse351000351falsefalsefalse15truefalsefalse1800018falsefalsefalse16truefalsefalse1700017falsefalsefalse17truefalsefalse3400034falsefalsefalse18truefalsefalse2700027falsefalsefalse19truefalsefalse52210005221falsefalsefalse20truefalsefalse37900003790falsefalsefalse21truefalsefalse1030600010306falsefalsefalse22truefalsefalse75080007508falsefalsefalse23truefalsefalse548000548falsefalsefalse24truefalsefalse358000358falsefalsefalse25truefalsefalse10960001096falsefalsefalse26truefalsefalse716000716falsefalsefalse27truefalsefalse-108000-108falsefalsefalse28truefalsefalse-63000-63falsefalsefalse29truefalsefalse-142000-142falsefalsefalse30truefalsefalse-122000-122falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of gains or losses recognized in net periodic benefit cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Amortization of net loss (gain)7false 5us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19truefalsefalse00falsefalsefalse20truefalsefalse00falsefalsefalse21truefalsefalse00falsefalsefalse22truefalsefalse00falsefalsefalse23truefalsefalse00falsefalsefalse24truefalsefalse00falsefalsefalse25truefalsefalse00falsefalsefalse26truefalsefalse00falsefalsefalse27truefalsefalse00falsefalsefalse28truefalsefalse1200012falsefalsefalse29truefalsefalse00falsefalsefalse30truefalsefalse2500025falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the transition obligation or asset recognized in net periodic benefit cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(6) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Amortization of transition obligation8false 4us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse17190001719USD$falsetruefalse8truefalsefalse14180001418USD$falsetruefalse9truefalsefalse29260002926USD$falsetruefalse10truefalsefalse27480002748USD$falsetruefalse11truefalsefalse12470001247USD$falsetruefalse12truefalsefalse982000982USD$falsetruefalse13truefalsefalse24930002493USD$falsetruefalse14truefalsefalse19640001964USD$falsetruefalse15truefalsefalse9600096USD$falsetruefalse16truefalsefalse128000128USD$falsetruefalse17truefalsefalse215000215USD$falsetruefalse18truefalsefalse254000254USD$falsetruefalse19truefalsefalse58500005850USD$falsetruefalse20truefalsefalse37430003743USD$falsetruefalse21truefalsefalse1119600011196USD$falsetruefalse22truefalsefalse74100007410USD$falsetruefalse23truefalsefalse14300001430USD$falsetruefalse24truefalsefalse12380001238USD$falsetruefalse25truefalsefalse28590002859USD$falsetruefalse26truefalsefalse24750002475USD$falsetruefalse27truefalsefalse-22000-22USD$falsetruefalse28truefalsefalse6900069USD$falsetruefalse29truefalsefalse5300053USD$falsetruefalse30truefalsefalse148000148USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Defined Benefit Plan, Net Periodic Benefit CostfalseRetirement Benefits Net Periodic Benefit Cost (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.pugetenergy.com/role/RetirementBenefitsNetPeriodicBenefitCostDetails308