XML 74 R52.htm IDEA: XBRL DOCUMENT
v3.21.2

Regulatory Matters - Schedule of Regulatory Assets (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Detail of regulatory assets |  |
Current | $ 420,802 | $ 291,713
Non-Current | 1,173,977 | 1,133,987
Pension |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 496,372 | 469,953
Deferred fuel and purchased power |  |
Detail of regulatory assets |  |
Current | 300,912 | 175,835
Non-Current | 0 | 0
Income taxes — allowance for funds used during construction (“AFUDC”) equity |  |
Detail of regulatory assets |  |
Current | 7,169 | 7,169
Non-Current | 161,279 | 158,776
Retired power plant costs |  |
Detail of regulatory assets |  |
Current | 28,182 | 28,181
Non-Current | 100,123 | 114,214
Ocotillo deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 124,919 | 95,723
SCR deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 95,171 | 81,307
Deferred property taxes |  |
Detail of regulatory assets |  |
Current | 8,569 | 8,569
Non-Current | 45,342 | 49,626
Lost fixed cost recovery |  |
Detail of regulatory assets |  |
Current | 53,087 | 41,807
Non-Current | 0 | 0
Deferred compensation |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 35,806 | 36,195
Four Corners cost deferral |  |
Detail of regulatory assets |  |
Current | 8,077 | 8,077
Non-Current | 20,037 | 24,075
Income taxes — investment tax credit basis adjustment |  |
Detail of regulatory assets |  |
Current | 1,113 | 1,113
Non-Current | 23,807 | 24,291
Palo Verde VIEs (Note 6) |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 21,174 | 21,255
Coal reclamation |  |
Detail of regulatory assets |  |
Current | 1,068 | 1,068
Non-Current | 16,465 | 16,999
Loss on reacquired debt |  |
Detail of regulatory assets |  |
Current | 1,648 | 1,689
Non-Current | 10,128 | 10,877
Mead-Phoenix transmission line contributions in aid of construction (“CIAC”) |  |
Detail of regulatory assets |  |
Current | 332 | 332
Non-Current | 9,214 | 9,380
Tax expense adjustor mechanism |  |
Detail of regulatory assets |  |
Current | 7,956 | 6,226
Non-Current | 0 | 0
Demand side management |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 7,269 | 7,268
Tax expense of Medicare subsidy |  |
Detail of regulatory assets |  |
Current | 1,235 | 1,235
Non-Current | 3,167 | 3,704
TCA balancing account |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 1,903 | 0
Deferred fuel and purchased power — mark-to-market (Note 7) |  |
Detail of regulatory assets |  |
Current | 0 | 3,341
Non-Current | 0 | 9,244
PSA Interest |  |
Detail of regulatory assets |  |
Current | 133 | 4,355
Non-Current | 0 | 0
Other |  |
Detail of regulatory assets |  |
Current | 1,321 | 2,716
Non-Current | $ 1,801 | $ 1,100

X
- Definition The amount for the individual regulatory current asset including deferred fuel and purchased power as itemized in a table of regulatory current assets as of the end of the period. + References No definition available. + Details
Name: | pnw_RegulatoryAssetIncludingDeferredFuelAndPurchasedPowerRegulatoryAssetCurrent
Namespace Prefix: | pnw_
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_RegulatoryAssetLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_PensionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_DeferredFuelandPurchasedPowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_DeferredIncomeTaxChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_RetiredPowerPlantCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_OctotilloDeferralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_SCRDeferralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_DeferredPropertyTaxesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_LostFixedCostRecoveryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_DeferredCompensationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_FourCornersCostDeferralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_InvestmentCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_CoalReclamationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_LossOnReacquiredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_MeadPhoenixtransmissionlineCIACMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_TaxExpenseAdjustorMechanismMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_DemandSideManagementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_TaxExpenseOfMedicareSubsidyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_TransmissionCostAdjustorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_DeferredFuelAndPurchasedPowerMTMCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=pnw_PSAInterestMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_OtherRegulatoryAssetsLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |