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v3.23.2

Debt (Other Short-Term Borrowings) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Debt [Line Items] |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $ 391 | $ 441 | $ 793 | $ 577
Average amount outstanding (based on daily outstanding balances) | $ 88 | $ 337 | $ 330 | $ 390
Weighted average interest rates | 5.30% | 1.00% | 4.80% | 0.60%
IPL [Member] |  |  |  |
Debt [Line Items] |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $ 70 | $ 0 | $ 70 | $ 0
Average amount outstanding (based on daily outstanding balances) | $ 6 | $ 0 | $ 3 | $ 0
Weighted average interest rates | 5.30% | 0.00% | 5.30% | 0.00%
WPL [Member] |  |  |  |
Debt [Line Items] |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $ 91 | $ 222 | $ 349 | $ 252
Average amount outstanding (based on daily outstanding balances) | $ 18 | $ 166 | $ 160 | $ 185
Weighted average interest rates | 5.20% | 0.90% | 4.80% | 0.50%

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