Leases (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) lease_renewal_period_option
Leases [Line Items]
Finance lease liabilities arising from obtaining leased assets	$ 125
WPL [Member]
Leases [Line Items]
Finance lease liabilities arising from obtaining leased assets	$ 125
Sheboygan Falls Energy Facility [Member] \| WPL [Member]
Leases [Line Items]
Finance lease, renewal options (in number of renewal periods) \| lease_renewal_period_option	2

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(2)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

Name:	us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration