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Related Parties (Tables) | 3 Months Ended
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Mar. 31, 2016
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
| 2016 |  | 2015 |  | 2016 |  | 2015
Corporate Services billings |  | $38 |  |  |  | $36 |  |  |  | $33 |  |  |  | $28 |
Sales credited | 1 |  |  | 4 |  |  | 1 |  |  | 6 |
Purchases billed | 96 |  |  | 79 |  |  | 19 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2016 |  | December 31, 2015 |  | March 31, 2016 |  | December 31, 2015
Net payables to Corporate Services | $100 |  | $93 |  | $59 |  | $54
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2016 |  | 2015
ATC billings to WPL |  | $27 |  |  |  | $25 |
WPL billings to ATC | 3 |  |  | 2 |
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
| 2016 |  | 2015 |  | 2016 |  | 2015
Corporate Services billings |  | $38 |  |  |  | $36 |  |  |  | $33 |  |  |  | $28 |
Sales credited | 1 |  |  | 4 |  |  | 1 |  |  | 6 |
Purchases billed | 96 |  |  | 79 |  |  | 19 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2016 |  | December 31, 2015 |  | March 31, 2016 |  | December 31, 2015
Net payables to Corporate Services | $100 |  | $93 |  | $59 |  | $54
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
| 2016 |  | 2015 |  | 2016 |  | 2015
Corporate Services billings |  | $38 |  |  |  | $36 |  |  |  | $33 |  |  |  | $28 |
Sales credited | 1 |  |  | 4 |  |  | 1 |  |  | 6 |
Purchases billed | 96 |  |  | 79 |  |  | 19 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2016 |  | December 31, 2015 |  | March 31, 2016 |  | December 31, 2015
Net payables to Corporate Services | $100 |  | $93 |  | $59 |  | $54
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2016 |  | 2015
ATC billings to WPL |  | $27 |  |  |  | $25 |
WPL billings to ATC | 3 |  |  | 2 |

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- Details
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- Details
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