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Related Parties (Tables) | 12 Months Ended
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Dec. 31, 2024
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Corporate Services billings | $183 |  | $181 |  | $181 |  | $171 |  | $163 |  | $155
Sales credited | — |  | 11 |  | 19 |  | 84 |  | 55 |  | 74
Purchases billed | 430 |  | 431 |  | 435 |  | 54 |  | 35 |  | 174
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2024 |  | 2023
IPL | $135 |  | $129
WPL | 64 |  | 72
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2024 |  | 2023 |  | 2022
ATC billings to WPL | $152 |  | $159 |  | $140
WPL billings to ATC | 16 |  | 20 |  | 18
IPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Corporate Services billings | $183 |  | $181 |  | $181 |  | $171 |  | $163 |  | $155
Sales credited | — |  | 11 |  | 19 |  | 84 |  | 55 |  | 74
Purchases billed | 430 |  | 431 |  | 435 |  | 54 |  | 35 |  | 174
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2024 |  | 2023
IPL | $135 |  | $129
WPL | 64 |  | 72
WPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Corporate Services billings | $183 |  | $181 |  | $181 |  | $171 |  | $163 |  | $155
Sales credited | — |  | 11 |  | 19 |  | 84 |  | 55 |  | 74
Purchases billed | 430 |  | 431 |  | 435 |  | 54 |  | 35 |  | 174
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2024 |  | 2023
IPL | $135 |  | $129
WPL | 64 |  | 72
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2024 |  | 2023 |  | 2022
ATC billings to WPL | $152 |  | $159 |  | $140
WPL billings to ATC | 16 |  | 20 |  | 18

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