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Related Parties (Tables) | 3 Months Ended
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Mar. 31, 2024
Related Party Transactions [Line Items] |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  |  |  |  |  | 2024 |  | 2023 |  |  |  |
Corporate Services billings | $43 |  | $40 |  |  |  |  |  | $40 |  | $36 |  |  |  |
Sales credited | — |  | 7 |  |  |  |  |  | 22 |  | 13 |  |  |  |
Purchases billed | 96 |  | 93 |  |  |  |  |  | 7 |  | 15 |  |  |  |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2024 |  | December 31, 2023 |  | March 31, 2024 |  | December 31, 2023
Net payables to Corporate Services | $132 |  | $129 |  | $70 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2024 |  | 2023 |  |  |  |
ATC billings to WPL | $37 |  | $34 |  |  |  |
WPL billings to ATC | 3 |  | 6 |  |  |  |
IPL [Member] |
Related Party Transactions [Line Items] |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  |  |  |  |  | 2024 |  | 2023 |  |  |  |
Corporate Services billings | $43 |  | $40 |  |  |  |  |  | $40 |  | $36 |  |  |  |
Sales credited | — |  | 7 |  |  |  |  |  | 22 |  | 13 |  |  |  |
Purchases billed | 96 |  | 93 |  |  |  |  |  | 7 |  | 15 |  |  |  |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2024 |  | December 31, 2023 |  | March 31, 2024 |  | December 31, 2023
Net payables to Corporate Services | $132 |  | $129 |  | $70 |  | $72
WPL [Member] |
Related Party Transactions [Line Items] |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2024 |  | 2023 |  |  |  |  |  | 2024 |  | 2023 |  |  |  |
Corporate Services billings | $43 |  | $40 |  |  |  |  |  | $40 |  | $36 |  |  |  |
Sales credited | — |  | 7 |  |  |  |  |  | 22 |  | 13 |  |  |  |
Purchases billed | 96 |  | 93 |  |  |  |  |  | 7 |  | 15 |  |  |  |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2024 |  | December 31, 2023 |  | March 31, 2024 |  | December 31, 2023
Net payables to Corporate Services | $132 |  | $129 |  | $70 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2024 |  | 2023 |  |  |  |
ATC billings to WPL | $37 |  | $34 |  |  |  |
WPL billings to ATC | 3 |  | 6 |  |  |  |

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