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Receivables (Receivables Sold Under The Agreement) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Accounts Receivable [Line Items] |  |
Fair value of deferred proceeds | $ 214 | $ 188
IPL [Member] |  |
Accounts Receivable [Line Items] |  |
Fair value of deferred proceeds | 214 | 188
Financing Receivable [Member] | IPL [Member] |  |
Accounts Receivable [Line Items] |  |
Customer accounts receivable | 125 | 114
Unbilled utility revenues | 104 | 92
Receivables sold to third party | 229 | 206
Less: cash proceeds | 1 | 1
Deferred proceeds | 228 | 205
Less: allowance for expected credit losses | 14 | 17
Fair value of deferred proceeds | 214 | 188
Financing Receivable [Member] | IPL [Member] | Financial Asset, Past Due |  |
Accounts Receivable [Line Items] |  |
Outstanding receivables past due | $ 22 | $ 27

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