XML 1056 R87.htm IDEA: XBRL DOCUMENT v2.4.1.9
Asset Retirement Obligations (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Changes attributable to:    
Asset retirement obligations, current $ 32,462,000us-gaap_AssetRetirementObligationCurrent $ 32,896,000us-gaap_AssetRetirementObligationCurrent
ARIZONA PUBLIC SERVICE COMPANY    
Change in asset retirement obligations    
Beginning balance 347,000,000us-gaap_AssetRetirementObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
357,000,000us-gaap_AssetRetirementObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Changes attributable to:    
Accretion expense 24,000,000us-gaap_AssetRetirementObligationAccretionExpense
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
24,000,000us-gaap_AssetRetirementObligationAccretionExpense
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Settlements (30,000,000)us-gaap_AssetRetirementObligationLiabilitiesSettled
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
(12,000,000)us-gaap_AssetRetirementObligationLiabilitiesSettled
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Assumed SCE's obligation 0pnw_AssetRetirementObligationAssumedDecommissioningObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
34,000,000pnw_AssetRetirementObligationAssumedDecommissioningObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Estimated cash flow revisions 44,000,000us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
(56,000,000)us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Newly incurred obligation 6,000,000pnw_AssetRetirementObligationNewlyIncurredObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
0pnw_AssetRetirementObligationNewlyIncurredObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Ending balance 391,000,000us-gaap_AssetRetirementObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
347,000,000us-gaap_AssetRetirementObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Asset retirement obligations, current 32,462,000us-gaap_AssetRetirementObligationCurrent
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
32,896,000us-gaap_AssetRetirementObligationCurrent
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
Four Corners Units 1 Through 3 | ARIZONA PUBLIC SERVICE COMPANY    
Changes attributable to:    
Estimated cash flow revisions 24,000,000us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_FourCornersUnits1Through3Member
4,000,000us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_FourCornersUnits1Through3Member
Solar Facility | ARIZONA PUBLIC SERVICE COMPANY    
Changes attributable to:    
Newly incurred obligation 6,000,000pnw_AssetRetirementObligationNewlyIncurredObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_SolarFacilityMember
 
Palo Verde Nuclear Facilities and Certain other Generation Transmission and Distribution Assets | ARIZONA PUBLIC SERVICE COMPANY    
Changes attributable to:    
Estimated cash flow revisions 20,000,000us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_PaloVerdeNuclearFacilitiesAndCertainOtherGenerationTransmissionAndDistributionAssetsMember
52,000,000us-gaap_AssetRetirementObligationRevisionOfEstimate
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_PaloVerdeNuclearFacilitiesAndCertainOtherGenerationTransmissionAndDistributionAssetsMember
Four Corners | ARIZONA PUBLIC SERVICE COMPANY    
Changes attributable to:    
Assumed SCE's obligation   $ 34,000,000pnw_AssetRetirementObligationAssumedDecommissioningObligation
/ dei_LegalEntityAxis
= pnw_ArizonaPublicServiceCompanyMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pnw_FourCornersMember