Regulatory Matters - Retail Rate Case Filing (Details)	Oct. 27, 2021 USD ($)	Aug. 02, 2021 USD ($)	Nov. 06, 2020 USD ($)	Oct. 31, 2019 USD ($) $ / kWh GW	Jun. 30, 2019 USD ($)	Aug. 13, 2018 USD ($)	Mar. 27, 2017 USD ($) $ / kWh	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 04, 2020 USD ($)	Oct. 02, 2020 USD ($)
Residential Utility Consumer Office
Public Utilities, General Disclosures [Line Items]
Revenue increase (decrease)										$ (50,100,000)	$ (20,800,000)
Average annual customer bill increase (decrease), percent										(1.52%)	(0.63%)
Recommended return on equity, percentage											8.74%
Increment of fair value rate, percentage											0.00%
ACC
Public Utilities, General Disclosures [Line Items]
Revenue increase (decrease)			$ 169,000,000							$ 59,800,000	$ 89,700,000
Average annual customer bill increase (decrease), percent			5.14%							1.82%	2.70%
Recommended return on equity, percentage			10.00%								9.40%
Alternative, percentage											0.30%
Increment of fair value rate, percentage			0.80%								0.00%
ACC | Coal Community Transition Plan
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders			$ 25,000,000						$ 25,200,000
Amount funded by customers, term			10 years
Amount funded by customers			$ 100,000,000
ACC | Coal Community Transition Plan | Navajo Nation, Economic Development Organization
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders			$ 1,250,000
Amount funded by shareholders, term			5 years
ACC | Coal Community Transition Plan | Navajo Nation, Electrification Projects
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders			$ 10,000,000						$ 10,000,000
Amount funded by customers			10,000,000
ACC | Coal Community Transition Plan | Navajo Nation, Transmission Revenue Sharing
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders			$ 2,500,000
ACC | Coal Community Transition Plan | Navajo County Communities, Cholla Power Plant Closure
Public Utilities, General Disclosures [Line Items]
Amount funded by customers, term			5 years
Amount funded by customers			$ 12,000,000
ACC | Coal Community Transition Plan | Navajo Nation, Generation Station
Public Utilities, General Disclosures [Line Items]
Amount funded by customers			$ 3,700,000					$ 900,000
ACC | Arizona Public Service Company
Public Utilities, General Disclosures [Line Items]
Proposed annual revenue increase				$ 184,000,000		$ (86,500,000)
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission
Public Utilities, General Disclosures [Line Items]
Base rate decrease, elimination of tax expense adjustment mechanism				$ 115,000,000
Approximate percentage of increase in average customer bill				5.60%
Approximate percentage of increase in average residential customer bill				5.40%
Rate matter, cost base rate					$ 8,870,000,000
Base fuel rate (in dollars per kWh) | $ / kWh				0.030168
Rate matter, funding limited income crisis bill program				$ 1,250,000
Commercial customers, market pricing, threshold | GW				200
Revenue increase (decrease)		$ (111,000,000)
Recommended return on equity, percentage	8.70%	9.16%
Increment of fair value rate, percentage		0.30%
Reduction on equity percentage		0.03%
Effective fair value percentage		4.95%
Settlement agreement, net retail base rate increase							$ 94,600,000
Settlement agreement, non-fuel, non-depreciation, base rate increase							87,200,000
Fuel-related base rate decrease							53,600,000
Base rate increase, changes in depreciation schedules							$ 61,000,000
Authorized return on common equity (as a percent)							10.00%
Percentage of debt in capital structure							44.20%
Percentage of common equity in capital structure							55.80%
Resource comparison proxy for exported energy (in dollars per kWh) | $ / kWh							0.129
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo Nation, Economic Development Organization
Public Utilities, General Disclosures [Line Items]
Amount funded by customers, term		10 years
Amount funded by customers		$ 50,000,000
Disallowance of annual amortization percentage		15.00%
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo County Communities, Cholla Power Plant Closure
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders	$ 500,000	$ 5,000,000
Amount funded by shareholders, term	60 days	5 years
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo Nation, Hopi Tribe
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders	$ 1,000,000	$ 1,675,000
Amount funded by shareholders, term	60 days
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo Nation
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders	$ 10,000,000
Amount funded by shareholders, term	3 years
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo Nation, Hopi Reservation
Public Utilities, General Disclosures [Line Items]
Amount funded by shareholders	$ 1,250,000
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | Coal Community Transition Plan | Navajo Nation Reservation
Public Utilities, General Disclosures [Line Items]
Revenue increase (decrease)	4,800,000
Amount funded by shareholders	$ 1,250,000
ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission | AZ Sun II Program
Public Utilities, General Disclosures [Line Items]
Minimum annual renewable energy standard and tariff							$ 10,000,000
Maximum annual renewable energy standard and tariff							$ 15,000,000
Minimum | ACC | Arizona Public Service Company
Public Utilities, General Disclosures [Line Items]
Regulatory impact, operating results				$ 69,000,000
Minimum | ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission
Public Utilities, General Disclosures [Line Items]
Environmental surcharge cap rate (in dollars per kWh) | $ / kWh							0.00016
Maximum | ACC | Arizona Public Service Company | Retail Rate Case Filing with Arizona Corporation Commission
Public Utilities, General Disclosures [Line Items]
Environmental surcharge cap rate (in dollars per kWh) | $ / kWh							0.00050