v2.4.0.6

Related Parties (Tables) | 9 Months Ended
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Sep. 30, 2012
Related Party Transactions [Abstract] |
Sales Credited And Purchases Billed | The sales credited to and purchases billed to IPL and WPL for the three and nine months ended September 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Sales credited |  | $3 |  |  |  | $6 |  |  |  | $7 |  |  |  | $26 |  |  |  | $4 |  |  |  | $7 |  |  |  | $10 |  |  |  | $23 |
Purchases billed | 87 |  |  | 93 |  |  | 237 |  |  | 238 |  |  | 13 |  |  | 20 |  |  | 50 |  |  | 56 |
Corporate Services Billings | The amounts billed to IPL and WPL for the three and nine months ended September 30 were as follows (in millions):
| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Corporate Services billings |  | $34 |  |  |  | $37 |  |  |  | $97 |  |  |  | $117 |  |  |  | $26 |  |  |  | $29 |  |  |  | $76 |  |  |  | $93 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| September 30, 2012 |  | December 31, 2011 |  | September 30, 2012 |  | December 31, 2011
Net payables to Corporate Services |  | $80 |  |  |  | $82 |  |  |  | $49 |  |  |  | $48 |
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2012 |  | 2011 |  | 2012 |  | 2011
ATC billings to WPL |  | $22 |  |  |  | $23 |  |  |  | $67 |  |  |  | $67 |
WPL billings to ATC | 3 |  |  | 2 |  |  | 7 |  |  | 8 |

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- Details
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