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Related Parties (Tables) | 3 Months Ended
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Mar. 31, 2015
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
| 2015 |  | 2014 |  | 2015 |  | 2014
Corporate Services billings |  | $36 |  |  |  | $33 |  |  |  | $28 |  |  |  | $28 |
Sales credited | 4 |  |  | 2 |  |  | 6 |  |  | (1 | )
Purchases billed | 79 |  |  | 99 |  |  | 14 |  |  | 30 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2015 |  | December 31, 2014 |  | March 31, 2015 |  | December 31, 2014
Net payables to Corporate Services | $85 |  | $84 |  | $52 |  | $58
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2015 |  | 2014
ATC billings to WPL |  | $25 |  |  |  | $24 |
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
| 2015 |  | 2014 |  | 2015 |  | 2014
Corporate Services billings |  | $36 |  |  |  | $33 |  |  |  | $28 |  |  |  | $28 |
Sales credited | 4 |  |  | 2 |  |  | 6 |  |  | (1 | )
Purchases billed | 79 |  |  | 99 |  |  | 14 |  |  | 30 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2015 |  | December 31, 2014 |  | March 31, 2015 |  | December 31, 2014
Net payables to Corporate Services | $85 |  | $84 |  | $52 |  | $58
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
| 2015 |  | 2014 |  | 2015 |  | 2014
Corporate Services billings |  | $36 |  |  |  | $33 |  |  |  | $28 |  |  |  | $28 |
Sales credited | 4 |  |  | 2 |  |  | 6 |  |  | (1 | )
Purchases billed | 79 |  |  | 99 |  |  | 14 |  |  | 30 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2015 |  | December 31, 2014 |  | March 31, 2015 |  | December 31, 2014
Net payables to Corporate Services | $85 |  | $84 |  | $52 |  | $58
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2015 |  | 2014
ATC billings to WPL |  | $25 |  |  |  | $24 |
WPL billings to ATC | 2 |  |  | 3 |

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