Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2017
Income Taxes
Reduction in net deferred income tax liabilities				$ 1,140
Income tax benefit		$ 31	$ 31
Amortization period		28 years 6 months
Income tax expense attributable to non controlling interests		$ 0
Interest expense to be received on the underpayment of income taxes		1
Increase (decrease) in deferred income taxes due to regulation adoption		42
Arizona Public Service Company
Income Taxes
Increase (decrease) in deferred income taxes due to regulation adoption		9
Federal
Income Taxes
Income tax benefit	$ 14
General business tax credit carryforwards		51
State
Income Taxes
State credit carryforwards net of federal benefit		42
Arizona net operating loss carryforwards net of federal benefit		6
State | Arizona Public Service Company
Income Taxes
State credit carryforwards net of federal benefit		24
Arizona net operating loss carryforwards net of federal benefit		$ 4