Income Taxes - Summary of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax [Line Items]
Tax positions, that if recognized, would decrease our effective tax rate	$ 25,714	$ 22,813	$ 19,504
Unrecognized tax benefit interest expense/(benefit) recognized	266	459	(780)
Unrecognized tax benefit interest accrued	1,855	1,589	1,130
ARIZONA PUBLIC SERVICE COMPANY
Income Tax [Line Items]
Tax positions, that if recognized, would decrease our effective tax rate	25,714	22,813	19,504
Unrecognized tax benefit interest expense/(benefit) recognized	266	459	(780)
Unrecognized tax benefit interest accrued	$ 1,855	$ 1,589	$ 1,130