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v3.23.1

Receivables (Narrative) (Details) $ in Millions | 3 Months Ended
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Mar. 31, 2023 USD ($)
Receivables [Line Items] |
Gross write-offs for accounts receivable, originated in 2022 | $ 5
IPL [Member] |
Receivables [Line Items] |
Gross write-offs for accounts receivable, originated in 2022 | 3
WPL [Member] |
Receivables [Line Items] |
Gross write-offs for accounts receivable, originated in 2022 | 2
Receivables Sold [Member] | IPL [Member] |
Receivables [Line Items] |
Available capacity | 21
Receivables Sold [Member] | IPL [Member] | Financial Asset, Past Due [Member] |
Receivables [Line Items] |
Outstanding receivables past due | $ 26

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