2.4.0.8009030 - Disclosure - REGULATORY ACTIONS, Deferred Energy (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$AS_OF_Jun30_2013http://www.sec.gov/CIK0000741508instant2013-06-30T00:00:000001-01-01T00:00:00USDollarStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$AS_OF_Dec31_2012http://www.sec.gov/CIK0000741508instant2012-12-31T00:00:000001-01-01T00:00:00USDollarStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4nve_NevadaDeferredEnergyAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Nevada Deferred Energy2false 5nve_NevadaDeferredEnergyCostsnve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTotalLabel1truefalsefalse1728400017284USD$falsetruefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net balance related to deferred energy costs regulated in the State of Nevada.No definition available.true2Nevada Deferred Energy Balance at period end3false 5nve_AmortizationOfDeferredEnergyCostsnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse9413400094134USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe cumulative amount of amortization of deferred energy costs during the period.No definition available.false2Amortization4false 5nve_CumulativeBalancenve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-151880000-151880USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCumulative deferred energy balance as filed with the PUCN.No definition available.false2Cumulative balance as filed5false 5nve_DeferredEnergyUnderCollectionnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse7503000075030[1]USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryUnder collections of energy costs due to higher energy costs than those included in current rates. These under collections will be subject to prudency review and subsequent recovery from ratepayers in future filings.No definition available.false2Deferred Energy Under Collection6false 4nve_ReinstatementOfDeferredEnergynve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse9510300095103USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDeferred energy costs reinstated effective in June 2007 to be recovered over 10 years.No definition available.false2Reinstatement of deferred energy (effective 6/07, 10 years)7false 4nve_TotalDeferredEnergyCostsNetnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse112387000112387USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net carrying amount as of the balance sheet date of deferred energy assets and liabilities.No definition available.true2Total Deferred Energy8true 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These under collections will be subject to prudency review and subsequent recovery from ratepayers in future filings.No definition available.false2Deferred Energy Under Collection20false 4nve_ReinstatementOfDeferredEnergynve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse9510300095103USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDeferred energy costs reinstated effective in June 2007 to be recovered over 10 years.No definition available.false2Reinstatement of deferred energy (effective 6/07, 10 years)21false 4nve_TotalDeferredEnergyCostsNetnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse107498000107498USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net carrying amount as of the balance sheet date of deferred energy assets and liabilities.No definition available.true2Total Deferred Energy22true 4nve_DeferredAssetsAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Deferred Assets23false 5nve_DeferredEnergyCostsElectricNonCurrentnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse8010900080109USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of capitalized electric costs of a regulated entity that are expected to be recoverable through rate adjustments after one year or beyond the normal operating cycle if longer.No definition available.false2Deferred energy24false 5nve_DeferredEnergyElectricCurrentnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse2738900027389USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of capitalized electric costs of a regulated entity that are expected to be recoverable through rate adjustments within one year.No definition available.false2Deferred Energy Electric Current25false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse4false USDtruefalse$AS_OF_Jun30_2013_us-gaap_StatementBusinessSegmentsAxis_SppcElectricMemberhttp://www.sec.gov/CIK0000741508instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseSPPC Electric [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldinve_SppcElectricMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUSDollarStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0SPPC Electric [Member]26true 4nve_NevadaDeferredEnergyAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Nevada Deferred Energy27false 5nve_NevadaDeferredEnergyCostsnve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTotalLabel1truefalsefalse27330002733USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net balance related to deferred energy costs regulated in the State of Nevada.No definition available.true2Nevada Deferred Energy Balance at period end28false 5nve_AmortizationOfDeferredEnergyCostsnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1919600019196USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe cumulative amount of amortization of deferred energy costs during the period.No definition available.false2Amortization29false 5nve_CumulativeBalancenve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-32693000-32693USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCumulative deferred energy balance as filed with the PUCN.No definition available.false2Cumulative balance as filed30false 5nve_DeferredEnergyUnderCollectionnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse1623000016230[1]USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryUnder collections of energy costs due to higher energy costs than those included in current rates. These under collections will be subject to prudency review and subsequent recovery from ratepayers in future filings.No definition available.false2Deferred Energy Under Collection31false 4nve_ReinstatementOfDeferredEnergynve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDeferred energy costs reinstated effective in June 2007 to be recovered over 10 years.No definition available.false2Reinstatement of deferred energy (effective 6/07, 10 years)32false 4nve_TotalDeferredEnergyCostsNetnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse27330002733USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net carrying amount as of the balance sheet date of deferred energy assets and liabilities.No definition available.true2Total Deferred Energy33true 4nve_DeferredAssetsAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Deferred Assets34false 5nve_DeferredEnergyElectricCurrentnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse27330002733USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of capitalized electric costs of a regulated entity that are expected to be recoverable through rate adjustments within one year.No definition available.false2Deferred Energy Electric Current35false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false USDtruefalse$AS_OF_Jun30_2013_us-gaap_StatementBusinessSegmentsAxis_SppcGasMemberhttp://www.sec.gov/CIK0000741508instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseSPPC Gas [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldinve_SppcGasMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUSDollarStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0SPPC Gas [Member]36true 4nve_NevadaDeferredEnergyAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Nevada Deferred Energy37false 5nve_NevadaDeferredEnergyCostsnve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTotalLabel1truefalsefalse21560002156USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net balance related to deferred energy costs regulated in the State of Nevada.No definition available.true2Nevada Deferred Energy Balance at period end38false 5nve_AmortizationOfDeferredEnergyCostsnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1705100017051USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe cumulative amount of amortization of deferred energy costs during the period.No definition available.false2Amortization39false 5nve_CumulativeBalancenve_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-18070000-18070USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCumulative deferred energy balance as filed with the PUCN.No definition available.false2Cumulative balance as filed40false 5nve_DeferredEnergyUnderCollectionnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse31750003175[1]USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryUnder collections of energy costs due to higher energy costs than those included in current rates. These under collections will be subject to prudency review and subsequent recovery from ratepayers in future filings.No definition available.false2Deferred Energy Under Collection41false 4nve_ReinstatementOfDeferredEnergynve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDeferred energy costs reinstated effective in June 2007 to be recovered over 10 years.No definition available.false2Reinstatement of deferred energy (effective 6/07, 10 years)42false 4nve_TotalDeferredEnergyCostsNetnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse21560002156USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net carrying amount as of the balance sheet date of deferred energy assets and liabilities.No definition available.true2Total Deferred Energy43true 4nve_DeferredAssetsAbstractnve_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Deferred Assets44false 5nve_DeferredEnergyCostsElectricNonCurrentnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse11650001165USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of capitalized electric costs of a regulated entity that are expected to be recoverable through rate adjustments after one year or beyond the normal operating cycle if longer.No definition available.false2Deferred energy45false 5nve_DeferredEnergyGasCurrentnve_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse991000991USD$falsetruefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying 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.No definition available.false2Deferred Energy Gas Current1These deferred energy under collections are subject to quarterly rate resets as discussed in Note 1, Summary of Significant AccountingPolicies, Deferred Energy Accounting, of the Notes to Financial Statements in the 2012 Form 10-K. falseREGULATORY ACTIONS, Deferred Energy (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://nvenergy.com/role/DisclosureREGULATORYACTIONSDeferredEnergyDetails245