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Related Parties (Tables) | 9 Months Ended
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Sep. 30, 2023
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
| 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Corporate Services billings | $46 |  | $45 |  | $134 |  | $136 |  | $40 |  | $39 |  | $120 |  | $117
Sales credited | 3 |  | 11 |  | 11 |  | 11 |  | 23 |  | 31 |  | 45 |  | 62
Purchases billed | 133 |  | 119 |  | 320 |  | 342 |  | 5 |  | 42 |  | 21 |  | 103
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2023 |  | December 31, 2022 |  | September 30, 2023 |  | December 31, 2022
Net payables to Corporate Services | $136 |  | $103 |  | $71 |  | $56
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
| 2023 |  | 2022 |  | 2023 |  | 2022
ATC billings to WPL | $41 |  | $38 |  | $119 |  | $107
WPL billings to ATC | 5 |  | 6 |  | 16 |  | 14
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
| 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Corporate Services billings | $46 |  | $45 |  | $134 |  | $136 |  | $40 |  | $39 |  | $120 |  | $117
Sales credited | 3 |  | 11 |  | 11 |  | 11 |  | 23 |  | 31 |  | 45 |  | 62
Purchases billed | 133 |  | 119 |  | 320 |  | 342 |  | 5 |  | 42 |  | 21 |  | 103
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2023 |  | December 31, 2022 |  | September 30, 2023 |  | December 31, 2022
Net payables to Corporate Services | $136 |  | $103 |  | $71 |  | $56
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
| 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Corporate Services billings | $46 |  | $45 |  | $134 |  | $136 |  | $40 |  | $39 |  | $120 |  | $117
Sales credited | 3 |  | 11 |  | 11 |  | 11 |  | 23 |  | 31 |  | 45 |  | 62
Purchases billed | 133 |  | 119 |  | 320 |  | 342 |  | 5 |  | 42 |  | 21 |  | 103
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2023 |  | December 31, 2022 |  | September 30, 2023 |  | December 31, 2022
Net payables to Corporate Services | $136 |  | $103 |  | $71 |  | $56
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
| 2023 |  | 2022 |  | 2023 |  | 2022
ATC billings to WPL | $41 |  | $38 |  | $119 |  | $107
WPL billings to ATC | 5 |  | 6 |  | 16 |  | 14

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