2.4.0.82406403 - Disclosure - Retirement Benefits Change in Net Benefit Obligation (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2013-01-01T00:00:002013-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012Q4YTD_us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis_us-gaap_PensionPlansDefinedBenefitMemberhttp://www.sec.gov/CIK0001085392duration2012-01-01T00:00:002012-12-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse1false USDtruefalse$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$nanafalse0Qualified Pension Benefits [Member]2true 4us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]3false 5us-gaap_DefinedBenefitPlanBenefitObligationus-gaap_truecreditinstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1truefalsefalse616290000616290USD$falsetruefalse2truefalsefalse565997000565997USD$falsetruefalsexbrli:monetaryItemTypemonetary1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a -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 (a) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 6 -Subparagraph a -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph E1 -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. false2Benefit obligation at beginning of period4false 5us-gaap_DefinedBenefitPlanServiceCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse96420009642USD$falsefalsefalse2truefalsefalse1692600016926USD$falsefalsefalsexbrli: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 cost5false 5us-gaap_DefinedBenefitPlanInterestCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse1237700012377USD$falsefalsefalse2truefalsefalse2598600025986USD$falsefalsefalsexbrli: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 cost6false 5us-gaap_DefinedBenefitPlanPlanAmendmentsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.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 a -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 Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520782 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520743 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)(7) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Amendments7false 5us-gaap_DefinedBenefitPlanActuarialGainLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse34360003436USD$falsefalsefalse2truefalsefalse4091400040914USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of gain (loss) from a decision to temporarily deviate from the substantive plan, or from a change in benefit obligation or plan asset value from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover or salary scale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Gain or Loss -URI http://asc.fasb.org/extlink&oid=6514294 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Gain or Loss -URI http://asc.fasb.org/extlink&oid=6749293 false2Actuarial loss/(gain)8false 5us-gaap_DefinedBenefitPlanBenefitsPaidus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-23250000-23250USD$falsefalsefalse2truefalsefalse-33533000-33533USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a, b -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 -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 3: 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 4: 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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506267 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506309 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS106-2 -Paragraph 22 -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. false2Benefits paid9false 5us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceivedus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS106-2 -Paragraph 20, 21, 22 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Medicare part D subsidiary received10false 5us-gaap_DefinedBenefitPlanBenefitObligationus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse618495000618495USD$falsefalsefalse2truefalsefalse616290000616290USD$falsefalsefalsexbrli:monetaryItemTypemonetary1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a -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 (a) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 6 -Subparagraph a -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph E1 -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. false2Benefit obligation at end of period11false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3false 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$nanafalse0SERP Pension Benefits [Member]12true 4us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]13false 5us-gaap_DefinedBenefitPlanBenefitObligationus-gaap_truecreditinstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1truefalsefalse5179500051795USD$falsefalsefalse2truefalsefalse4837000048370USD$falsefalsefalsexbrli:monetaryItemTypemonetary1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a -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 (a) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 6 -Subparagraph a -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph E1 -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. false2Benefit obligation at beginning of period14false 5us-gaap_DefinedBenefitPlanServiceCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse749000749USD$falsefalsefalse2truefalsefalse10730001073USD$falsefalsefalsexbrli: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 cost15false 5us-gaap_DefinedBenefitPlanInterestCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse10230001023USD$falsefalsefalse2truefalsefalse21520002152USD$falsefalsefalsexbrli: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 cost16false 5us-gaap_DefinedBenefitPlanPlanAmendmentsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse-122000-122USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520782 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520743 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 false2Amendments17false 5us-gaap_DefinedBenefitPlanActuarialGainLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse54830005483USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of gain (loss) from a decision to temporarily deviate from the substantive plan, or from a change in benefit obligation or plan asset value from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover or salary scale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Gain or Loss -URI http://asc.fasb.org/extlink&oid=6514294 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Gain or Loss -URI http://asc.fasb.org/extlink&oid=6749293 false2Actuarial loss/(gain)18false 5us-gaap_DefinedBenefitPlanBenefitsPaidus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-3182000-3182USD$falsefalsefalse2truefalsefalse-5161000-5161USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. 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Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 3: 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 4: 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. 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Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506267 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506309 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS106-2 -Paragraph 22 -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. false2Benefits paid19false 5us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceivedus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS106-2 -Paragraph 20, 21, 22 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph E1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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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. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Benefits paid29false 5us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceivedus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse125000125USD$falsefalsefalse2truefalsefalse670000670USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS106-2 -Paragraph 20, 21, 22 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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