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Related Parties (Tables) | 6 Months Ended
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Jun. 30, 2021
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
| 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Corporate Services billings | $48 |  | $44 |  | $88 |  | $81 |  | $41 |  | $35 |  | $76 |  | $67
Sales credited | 4 |  | 10 |  | 5 |  | 25 |  | 6 |  | 2 |  | 7 |  | 4
Purchases billed | 99 |  | 57 |  | 242 |  | 138 |  | 21 |  | 20 |  | 47 |  | 40
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2021 |  | December 31, 2020 |  | June 30, 2021 |  | December 31, 2020
Net payables to Corporate Services | $126 |  | $110 |  | $72 |  | $73
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
| 2021 |  | 2020 |  | 2021 |  | 2020
ATC billings to WPL | $30 |  | $25 |  | $62 |  | $53
WPL billings to ATC | 6 |  | 3 |  | 9 |  | 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 and six months ended June 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Six Months |  | Three Months |  | Six Months
| 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Corporate Services billings | $48 |  | $44 |  | $88 |  | $81 |  | $41 |  | $35 |  | $76 |  | $67
Sales credited | 4 |  | 10 |  | 5 |  | 25 |  | 6 |  | 2 |  | 7 |  | 4
Purchases billed | 99 |  | 57 |  | 242 |  | 138 |  | 21 |  | 20 |  | 47 |  | 40
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2021 |  | December 31, 2020 |  | June 30, 2021 |  | December 31, 2020
Net payables to Corporate Services | $126 |  | $110 |  | $72 |  | $73
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
| 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Corporate Services billings | $48 |  | $44 |  | $88 |  | $81 |  | $41 |  | $35 |  | $76 |  | $67
Sales credited | 4 |  | 10 |  | 5 |  | 25 |  | 6 |  | 2 |  | 7 |  | 4
Purchases billed | 99 |  | 57 |  | 242 |  | 138 |  | 21 |  | 20 |  | 47 |  | 40
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| June 30, 2021 |  | December 31, 2020 |  | June 30, 2021 |  | December 31, 2020
Net payables to Corporate Services | $126 |  | $110 |  | $72 |  | $73
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
| 2021 |  | 2020 |  | 2021 |  | 2020
ATC billings to WPL | $30 |  | $25 |  | $62 |  | $53
WPL billings to ATC | 6 |  | 3 |  | 9 |  | 6

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