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Receivables (Gross Write-offs for Accounts Receivable (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items] |
Gross write-offs for accounts receivable, originated in 2023 | $ 12
Gross write-offs for accounts receivable, originated in 2024 | 14
IPL [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Gross write-offs for accounts receivable, originated in 2023 | 8
Gross write-offs for accounts receivable, originated in 2024 | 9
WPL [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Gross write-offs for accounts receivable, originated in 2023 | 4
Gross write-offs for accounts receivable, originated in 2024 | $ 5

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