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Related Parties (Tables) | 12 Months Ended
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Dec. 31, 2023
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
| 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021
Corporate Services billings | $181 |  | $181 |  | $180 |  | $163 |  | $155 |  | $154
Sales credited | 11 |  | 19 |  | 22 |  | 55 |  | 74 |  | 23
Purchases billed | 431 |  | 435 |  | 441 |  | 35 |  | 174 |  | 116
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2023 |  | 2022
IPL | $129 |  | $103
WPL | 72 |  | 56
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2023 |  | 2022 |  | 2021
ATC billings to WPL | $159 |  | $140 |  | $122
WPL billings to ATC | 20 |  | 18 |  | 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
| 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021
Corporate Services billings | $181 |  | $181 |  | $180 |  | $163 |  | $155 |  | $154
Sales credited | 11 |  | 19 |  | 22 |  | 55 |  | 74 |  | 23
Purchases billed | 431 |  | 435 |  | 441 |  | 35 |  | 174 |  | 116
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2023 |  | 2022
IPL | $129 |  | $103
WPL | 72 |  | 56
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
| 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021
Corporate Services billings | $181 |  | $181 |  | $180 |  | $163 |  | $155 |  | $154
Sales credited | 11 |  | 19 |  | 22 |  | 55 |  | 74 |  | 23
Purchases billed | 431 |  | 435 |  | 441 |  | 35 |  | 174 |  | 116
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2023 |  | 2022
IPL | $129 |  | $103
WPL | 72 |  | 56
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2023 |  | 2022 |  | 2021
ATC billings to WPL | $159 |  | $140 |  | $122
WPL billings to ATC | 20 |  | 18 |  | 18

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