XML 81 R68.htm IDEA: XBRL DOCUMENT
v3.25.3

Regulatory Matters - Schedule of Regulatory Liabilities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Detail of regulatory liabilities |  |
Total regulatory liabilities | $ 1,963,994 | $ 2,062,233
Less: current regulatory liabilities | 194,094 | 206,955
Total non-current regulatory liabilities | 1,769,900 | 1,855,278
Asset retirement obligations and removal costs |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 314,510 | 358,403
Other postretirement benefits |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 226,043 | 238,113
Four Corners coal reclamation |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 97,857 | 77,532
Income taxes — deferred investment tax credit |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 63,663 | 66,327
Income taxes — change in rates |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 56,421 | 59,133
Renewable energy standard |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 43,190 | 68,523
Demand side management |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 30,591 | 23,927
Sundance maintenance |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 25,408 | 23,086
Spent nuclear fuel |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 22,357 | 26,818
Deferred fuel and purchased power — mark-to-market (Note 9) |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 15,600 | 0
TCA Balancing Account |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 10,413 | 14,834
Tax expense adjustor mechanism |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 3,889 | 4,343
Property tax deferral |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 3,143 | 4,785
Other |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 456 | 113
ACC | Excess deferred income taxes - Tax Cuts and Jobs Act |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | 849,886 | 888,896
FERC | Excess deferred income taxes - Tax Cuts and Jobs Act |  |
Detail of regulatory liabilities |  |
Total regulatory liabilities | $ 200,567 | $ 207,400

X
- Definition The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 405 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477571/980-405-25-1 + Details
Name: | us-gaap_RegulatoryLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_RegulatoryLiabilitiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 405 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477571/980-405-25-1 + Details
Name: | us-gaap_RegulatoryLiabilityCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_RegulatoryLiabilityNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_AssetRetirementObligationCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_PostretirementBenefitCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_FourCornersCoalReclamationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_IncomeTaxesChangeInRatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_RenewableEnergyProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_SundanceMaintenanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_SpentNuclearFuelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_TCABalancingAccountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_OtherRegulatoryLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=pnw_ArizonaCorporationCommissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=pnw_TaxCutsandJobsActof2017ExcessDeferredIncomeTaxesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=pnw_UnitedStatesFederalEnergyRegulatoryCommissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |