COMMON EQUITY - DIVIDEND RESTRICTIONS (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)
Dividend Payment Restrictions
Restricted retained earnings	$ 579
Public Service Commission of Wisconsin \| Minimum
Dividend Payment Restrictions
Common equity ratio required to be maintained (as a percent)	53.00%

A segregation of retained earnings which is unavailable for dividend distribution. Includes also retained earnings appropriated for loss contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant