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Related Parties (Tables) | 6 Months Ended
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Jun. 30, 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 and six months ended June 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Six Months |  | Three Months |  | Six Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $49 |  | $48 |  | $92 |  | $88 |  | $46 |  | $43 |  | $86 |  | $80
Sales credited | — |  | 1 |  | — |  | 8 |  | 14 |  | 10 |  | 36 |  | 22
Purchases billed | 105 |  | 94 |  | 201 |  | 187 |  | 16 |  | 2 |  | 23 |  | 17
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2024 |  | December 31, 2023 |  | June 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $138 |  | $129 |  | $67 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):
| Three Months |  | Six Months
| 2024 |  | 2023 |  | 2024 |  | 2023
ATC billings to WPL | $39 |  | $44 |  | $76 |  | $78
WPL billings to ATC | 4 |  | 5 |  | 7 |  | 11
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 and six months ended June 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Six Months |  | Three Months |  | Six Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $49 |  | $48 |  | $92 |  | $88 |  | $46 |  | $43 |  | $86 |  | $80
Sales credited | — |  | 1 |  | — |  | 8 |  | 14 |  | 10 |  | 36 |  | 22
Purchases billed | 105 |  | 94 |  | 201 |  | 187 |  | 16 |  | 2 |  | 23 |  | 17
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2024 |  | December 31, 2023 |  | June 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $138 |  | $129 |  | $67 |  | $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 and six months ended June 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Six Months |  | Three Months |  | Six Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $49 |  | $48 |  | $92 |  | $88 |  | $46 |  | $43 |  | $86 |  | $80
Sales credited | — |  | 1 |  | — |  | 8 |  | 14 |  | 10 |  | 36 |  | 22
Purchases billed | 105 |  | 94 |  | 201 |  | 187 |  | 16 |  | 2 |  | 23 |  | 17
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2024 |  | December 31, 2023 |  | June 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $138 |  | $129 |  | $67 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):
| Three Months |  | Six Months
| 2024 |  | 2023 |  | 2024 |  | 2023
ATC billings to WPL | $39 |  | $44 |  | $76 |  | $78
WPL billings to ATC | 4 |  | 5 |  | 7 |  | 11

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