Regulatory Matters - Schedule of Changes in The Deferred Fuel and Purchased Power Regulatory Asset (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Change in regulatory asset
Deferred fuel and purchased power costs — current period	$ 33,094	$ 90,305
Amounts charged to customers	(108,552)	(80,904)
APS
Change in regulatory asset
Deferred fuel and purchased power costs — current period	33,094	90,305
Amounts charged to customers	(108,552)	(80,904)
Power Supply Adjustor (PSA) | ACC | APS
Change in regulatory asset
Beginning balance	463,195	460,561
Deferred fuel and purchased power costs — current period	33,094	90,305
Amounts charged to customers	(108,552)	(80,904)
Ending balance	$ 387,737	$ 469,962