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Related Parties (Tables) | 9 Months Ended
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Sep. 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 nine months ended September 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $42 |  | $46 |  | $134 |  | $134 |  | $38 |  | $40 |  | $124 |  | $120
Sales credited | — |  | 3 |  | — |  | 11 |  | 29 |  | 23 |  | 66 |  | 45
Purchases billed | 130 |  | 133 |  | 332 |  | 320 |  | 18 |  | 5 |  | 41 |  | 21
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2024 |  | December 31, 2023 |  | September 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $131 |  | $129 |  | $72 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2024 |  | 2023 |  | 2024 |  | 2023
ATC billings to WPL | $39 |  | $41 |  | $115 |  | $119
WPL billings to ATC | 5 |  | 5 |  | 12 |  | 16
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 nine months ended September 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $42 |  | $46 |  | $134 |  | $134 |  | $38 |  | $40 |  | $124 |  | $120
Sales credited | — |  | 3 |  | — |  | 11 |  | 29 |  | 23 |  | 66 |  | 45
Purchases billed | 130 |  | 133 |  | 332 |  | 320 |  | 18 |  | 5 |  | 41 |  | 21
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2024 |  | December 31, 2023 |  | September 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $131 |  | $129 |  | $72 |  | $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 nine months ended September 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Corporate Services billings | $42 |  | $46 |  | $134 |  | $134 |  | $38 |  | $40 |  | $124 |  | $120
Sales credited | — |  | 3 |  | — |  | 11 |  | 29 |  | 23 |  | 66 |  | 45
Purchases billed | 130 |  | 133 |  | 332 |  | 320 |  | 18 |  | 5 |  | 41 |  | 21
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2024 |  | December 31, 2023 |  | September 30, 2024 |  | December 31, 2023
Net payables to Corporate Services | $131 |  | $129 |  | $72 |  | $72
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2024 |  | 2023 |  | 2024 |  | 2023
ATC billings to WPL | $39 |  | $41 |  | $115 |  | $119
WPL billings to ATC | 5 |  | 5 |  | 12 |  | 16

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