XML 112 R85.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Jointly-Owned Facilities (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Jul. 06, 2016
--- | --- | ---
4CA |  |
Interests in jointly-owned facilities |  |
Plant in Service | $ 110,000 |
Accumulated Depreciation | 79,000 |
Construction work in progress | $ 30,000 |
Palo Verde Units 1 and 3 | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 29.10% |
Plant in Service | $ 1,770,324 |
Accumulated Depreciation | 1,080,072 |
Construction work in progress | $ 17,615 |
Palo Verde Unit 2 | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 16.80% |
Plant in Service | $ 581,572 |
Accumulated Depreciation | 360,757 |
Construction work in progress | $ 9,717 |
Palo Verde Common | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 28.00% |
Plant in Service | $ 672,799 |
Accumulated Depreciation | 242,649 |
Construction work in progress | 62,479 |
Palo Verde Sale Leaseback | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Plant in Service | 351,050 |
Accumulated Depreciation | 237,535 |
Construction work in progress | $ 0 |
Four Corners Generating Station | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 63.00% |
Plant in Service | $ 934,837 |
Accumulated Depreciation | 578,924 |
Construction work in progress | $ 248,072 |
Navajo Generating Station Units 1, 2 and 3 | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 14.00% |
Plant in Service | $ 279,629 |
Accumulated Depreciation | 176,931 |
Construction work in progress | $ 5,761 |
Cholla Common Facilities | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 63.30% |
Plant in Service | $ 159,707 |
Accumulated Depreciation | 58,276 |
Construction work in progress | $ 806 |
ANPP 500kV System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 33.60% |
Plant in Service | $ 127,970 |
Accumulated Depreciation | 38,610 |
Construction work in progress | $ 2,291 |
Navajo Southern System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 22.50% |
Plant in Service | $ 62,135 |
Accumulated Depreciation | 20,491 |
Construction work in progress | $ 334 |
Palo Verde — Yuma 500kV System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 19.00% |
Plant in Service | $ 13,699 |
Accumulated Depreciation | 5,368 |
Construction work in progress | $ 408 |
Four Corners Switchyards | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 51.30% |
Plant in Service | $ 39,850 |
Accumulated Depreciation | 10,474 |
Construction work in progress | $ 1,044 |
Phoenix — Mead System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 17.10% |
Plant in Service | $ 39,330 |
Accumulated Depreciation | 13,725 |
Construction work in progress | $ 85 |
Palo Verde — Rudd 500kV System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 50.00% |
Plant in Service | $ 91,904 |
Accumulated Depreciation | 19,818 |
Construction work in progress | $ 227 |
Morgan — Pinnacle Peak System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 65.20% |
Plant in Service | $ 140,374 |
Accumulated Depreciation | 13,557 |
Construction work in progress | $ 0 |
Round Valley System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 50.00% |
Plant in Service | $ 515 |
Accumulated Depreciation | 127 |
Construction work in progress | $ 0 |
Palo Verde — Morgan System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 85.80% |
Plant in Service | $ 125,908 |
Accumulated Depreciation | 1,326 |
Construction work in progress | $ 28,949 |
Hassayampa — North Gila System | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 80.00% |
Plant in Service | $ 142,541 |
Accumulated Depreciation | 3,231 |
Construction work in progress | $ 0 |
Cholla 500kV Switchyard | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 85.70% |
Plant in Service | $ 5,078 |
Accumulated Depreciation | 1,201 |
Construction work in progress | $ 0 |
Saguaro 500kV Switchyard | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 75.00% |
Plant in Service | $ 20,456 |
Accumulated Depreciation | 12,426 |
Construction work in progress | $ 2 |
Cholla common construction facilities | ARIZONA PUBLIC SERVICE COMPANY |  |
Interests in jointly-owned facilities |  |
Percent Owned | 50.50% |
El Paso's Interest in Four Corners | 4CA |  |
Interests in jointly-owned facilities |  |
Ownership interest acquired | 7.00% | 7.00%

X
- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The period end amount owned by the reporting utility of a jointly owned utility plant in service. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 + Details
Name: | us-gaap_JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_JointlyOwnedUtilityPlantInterestsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The period end amount of construction work in progress at a jointly owned electricity generation plant. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 + Details
Name: | us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The period end amount of accumulated depreciation in a jointly owned electricity generation plant. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 + Details
Name: | us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 + Details
Name: | us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=pnw_A4CAcquisitionLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeUnits1And3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=pnw_ArizonaPublicServiceCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeUnit2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeCommonMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeSaleLeasebackMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_FourCornersUnits4And5Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_NavajoGeneratingStationUnits12And3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_ChollaCommonFacilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_ANPP500KVSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_NavajoSouthernSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeYuma500KVSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_FourCornersSwitchyardsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PhoenixMeadSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeEstrella500KVSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_MorganPinnaclePeakSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_RoundValleySystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_PaloVerdeMorganSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_HassayampaNorthGilaSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_Cholla500SwitchyardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_Saguaro500SwitchyardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=pnw_ChollaCommonFacilitiesConstructionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=pnw_ElPasosInterestinFourCornersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |