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Related Parties (Tables) | 3 Months Ended
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Mar. 31, 2018
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
| 2018 |  | 2017 |  | 2018 |  | 2017
Corporate Services billings |  | $41 |  |  |  | $39 |  |  |  | $33 |  |  |  | $31 |
Sales credited | 5 |  |  | 2 |  |  | 1 |  |  | — |
Purchases billed | 93 |  |  | 66 |  |  | 17 |  |  | 34 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2018 |  | December 31, 2017 |  | March 31, 2018 |  | December 31, 2017
Net payables to Corporate Services | $96 |  | $114 |  | $64 |  | $61
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2018 |  | 2017
ATC billings to WPL |  | $27 |  |  |  | $26 |
WPL billings to ATC | 2 |  |  | 3 |
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
| 2018 |  | 2017 |  | 2018 |  | 2017
Corporate Services billings |  | $41 |  |  |  | $39 |  |  |  | $33 |  |  |  | $31 |
Sales credited | 5 |  |  | 2 |  |  | 1 |  |  | — |
Purchases billed | 93 |  |  | 66 |  |  | 17 |  |  | 34 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2018 |  | December 31, 2017 |  | March 31, 2018 |  | December 31, 2017
Net payables to Corporate Services | $96 |  | $114 |  | $64 |  | $61
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
| 2018 |  | 2017 |  | 2018 |  | 2017
Corporate Services billings |  | $41 |  |  |  | $39 |  |  |  | $33 |  |  |  | $31 |
Sales credited | 5 |  |  | 2 |  |  | 1 |  |  | — |
Purchases billed | 93 |  |  | 66 |  |  | 17 |  |  | 34 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2018 |  | December 31, 2017 |  | March 31, 2018 |  | December 31, 2017
Net payables to Corporate Services | $96 |  | $114 |  | $64 |  | $61
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2018 |  | 2017
ATC billings to WPL |  | $27 |  |  |  | $26 |
WPL billings to ATC | 2 |  |  | 3 |

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- Details
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- Details
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