Asset Retirement Obligations - Narrative (Details) - APS $ in Millions	6 Months Ended
Jun. 30, 2023 USD ($)
Cholla
Asset Retirement Obligations
Asset retirement obligation, period increase	$ 36
Four Corners Coal-Fired Power Plant
Asset Retirement Obligations
Asset retirement obligation, period increase	$ 13

Amount of increase (decrease) in asset retirement obligations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration