Long-Term Debt and Liquidity Matters - Additional Information (Details) - USD ($)					12 Months Ended
	Nov. 19, 2020	Jun. 17, 2020	May 22, 2020	Jan. 15, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 23, 2020	Dec. 17, 2020	Dec. 16, 2020	Nov. 18, 2020	Sep. 11, 2020	Jun. 16, 2020	May 05, 2020
Long-Term Debt and Liquidity Matters [Line Items]
Repayment of long-term debt					$ 915,150,000	$ 600,000,000	$ 182,000,000
Issuance of long-term debt					$ 1,596,672,000	1,092,188,000	445,245,000
Maximum
Debt Provisions
Ratio of consolidated debt to consolidated capitalization (as a percent)					65.00%
Term loan
Long-Term Debt and Liquidity Matters [Line Items]
Notes issued								$ 150,000,000
Repayment of long-term debt		$ 150,000,000
Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Repayment of long-term debt					$ 450,000,000	0	0
Issuance of long-term debt					$ 496,950,000	0	150,000,000
Debt Provisions
Actual ratio of consolidated debt to total consolidated capitalization required to be maintained as per the debt covenant (as a percent)					54.00%
Pinnacle West | Term loan
Long-Term Debt and Liquidity Matters [Line Items]
Notes issued														$ 31,000,000
ARIZONA PUBLIC SERVICE COMPANY
Long-Term Debt and Liquidity Matters [Line Items]
Repayment of long-term debt					$ 465,150,000	600,000,000	182,000,000
Issuance of long-term debt					$ 1,099,722,000	$ 1,092,188,000	295,245,000
Debt Provisions
Actual ratio of consolidated debt to total consolidated capitalization required to be maintained as per the debt covenant (as a percent)					49.00%
Equity infusion from Pinnacle West					$ 150,000,000		$ 150,000,000
ARIZONA PUBLIC SERVICE COMPANY | ACC
Debt Provisions
Long term debt authorization									$ 7,500,000,000	$ 5,900,000,000
ARIZONA PUBLIC SERVICE COMPANY | Term loan
Long-Term Debt and Liquidity Matters [Line Items]
Repayment of long-term debt			$ 200,000,000
ARIZONA PUBLIC SERVICE COMPANY | Senior notes
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)				2.20%
Extinguishment of debt				$ 150,000,000
Senior unsecured notes | Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)					1.30%
Senior unsecured notes
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)		1.30%											2.25%
Senior unsecured notes | Senior notes
Long-Term Debt and Liquidity Matters [Line Items]
Notes issued		$ 500,000,000											$ 300,000,000
Senior unsecured notes | ARIZONA PUBLIC SERVICE COMPANY | Maximum
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)					6.88%
Senior unsecured notes | ARIZONA PUBLIC SERVICE COMPANY | Minimum
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)			3.35%		2.55%
Senior unsecured notes | ARIZONA PUBLIC SERVICE COMPANY | Senior notes
Long-Term Debt and Liquidity Matters [Line Items]
Notes issued	$ 405,000,000			$ 250,000,000							$ 300,000,000	$ 400,000,000
Interest rate (as a percent)	2.60%											2.65%
Extinguishment of debt			$ 600,000,000
Issuance of long-term debt	$ 105,000,000
City of Farmington, New Mexico Pollution Control Revenue Refunding Bond | ARIZONA PUBLIC SERVICE COMPANY
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)					4.70%
Repayment of long-term debt	49,400,000
City of Farmington, New Mexico Pollution Control Revenue Refunding Bond, 1994 Series B | ARIZONA PUBLIC SERVICE COMPANY
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)					4.70%
Repayment of long-term debt	$ 65,750,000