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Related Parties (Tables) | 12 Months Ended
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Dec. 31, 2017
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2017 |  | 2016 |  | 2015 |  | 2017 |  | 2016 |  | 2015
Corporate Services billings |  | $177 |  |  |  | $161 |  |  |  | $150 |  |  |  | $135 |  |  |  | $133 |  |  |  | $121 |
Sales credited | 23 |  |  | 8 |  | 10 |  | 13 |  |  | 7 |  | 24
Purchases billed | 364 |  |  | 433 |  | 366 |  | 115 |  |  | 102 |  | 66
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2017 |  | 2016
IPL |  | $114 |  |  |  | $104 |
WPL | 61 |  |  | 72 |
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2017 |  | 2016 |  | 2015
ATC billings to WPL |  | $105 |  |  |  | $110 |  |  |  | $101 |
WPL billings to ATC | 10 |  |  | 13 |  |  | 13 |
IPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2017 |  | 2016 |  | 2015 |  | 2017 |  | 2016 |  | 2015
Corporate Services billings |  | $177 |  |  |  | $161 |  |  |  | $150 |  |  |  | $135 |  |  |  | $133 |  |  |  | $121 |
Sales credited | 23 |  |  | 8 |  | 10 |  | 13 |  |  | 7 |  | 24
Purchases billed | 364 |  |  | 433 |  | 366 |  | 115 |  |  | 102 |  | 66
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2017 |  | 2016
IPL |  | $114 |  |  |  | $104 |
WPL | 61 |  |  | 72 |
WPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases were as follows (in millions):
| IPL |  | WPL
| 2017 |  | 2016 |  | 2015 |  | 2017 |  | 2016 |  | 2015
Corporate Services billings |  | $177 |  |  |  | $161 |  |  |  | $150 |  |  |  | $135 |  |  |  | $133 |  |  |  | $121 |
Sales credited | 23 |  |  | 8 |  | 10 |  | 13 |  |  | 7 |  | 24
Purchases billed | 364 |  |  | 433 |  | 366 |  | 115 |  |  | 102 |  | 66
Net Intercompany Payables | As of December 31, net intercompany payables to Corporate Services were as follows (in millions):
| 2017 |  | 2016
IPL |  | $114 |  |  |  | $104 |
WPL | 61 |  |  | 72 |
Related Amounts Billed Between Parties | The related amounts billed between the parties were as follows (in millions):
| 2017 |  | 2016 |  | 2015
ATC billings to WPL |  | $105 |  |  |  | $110 |  |  |  | $101 |
WPL billings to ATC | 10 |  |  | 13 |  |  | 13 |

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- Details
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- Details
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