Retirement Plans and Other Postretirement Benefits - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Ultimate healthcare cost trend rate (pre-65 participants)	4.75%	4.75%
Initial and ultimate healthcare cost trend rate (post-65 participants)	2.00%	2.00%
Funded percentage (more than)	100.00%	100.00%
Partnership funding commitments, contribution amount (up to)	$ 50,000,000
Partnership funding commitments, funded amount	$ 38,000,000
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return on plan assets for next fiscal year (as a percent)	7.00%
Retiree medical cost reimbursement	$ 23,000,000	$ 26,000,000	$ 24,000,000
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return on plan assets for next fiscal year (as a percent)	6.90%
Employer contributions			100,000,000
Minimum contributions under MAP-21	$ 0
Pinnacle West
Defined Benefit Plan Disclosure [Line Items]
Expenses recorded for the defined contribution savings plan	$ 12,000,000	$ 12,000,000	$ 12,000,000
Arizona Public Service Company
Defined Benefit Plan Disclosure [Line Items]
APS's employees share of total cost of the plans (as a percent)	99.00%