XML 67 R35.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Related Parties (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2014
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases billed for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013
Corporate Services billings |  | $33 |  |  |  | $32 |  |  |  | $28 |  |  |  | $26 |
Sales credited | 2 |  |  | 2 |  |  | (1 | ) |  | 3 |
Purchases billed | 99 |  |  | 76 |  |  | 30 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2014 |  | December 31, 2013 |  | March 31, 2014 |  | December 31, 2013
Net payables to Corporate Services | $35 |  | $62 |  | $41 |  | $46
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2014 |  | 2013
ATC billings to WPL |  | $24 |  |  |  | $24 |
WPL billings to ATC | 3 |  |  | 3 |
IPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases billed for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013
Corporate Services billings |  | $33 |  |  |  | $32 |  |  |  | $28 |  |  |  | $26 |
Sales credited | 2 |  |  | 2 |  |  | (1 | ) |  | 3 |
Purchases billed | 99 |  |  | 76 |  |  | 30 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2014 |  | December 31, 2013 |  | March 31, 2014 |  | December 31, 2013
Net payables to Corporate Services | $35 |  | $62 |  | $41 |  | $46
WPL [Member] |
Related Party Transaction [Line Items] |
Services Provided, Sales Credited And Purchases Billed | The amounts billed for services provided, sales credited and purchases billed for the three months ended March 31 were as follows (in millions):
| IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013
Corporate Services billings |  | $33 |  |  |  | $32 |  |  |  | $28 |  |  |  | $26 |
Sales credited | 2 |  |  | 2 |  |  | (1 | ) |  | 3 |
Purchases billed | 99 |  |  | 76 |  |  | 30 |  |  | 14 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions):
| IPL |  | WPL
| March 31, 2014 |  | December 31, 2013 |  | March 31, 2014 |  | December 31, 2013
Net payables to Corporate Services | $35 |  | $62 |  | $41 |  | $46
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
| 2014 |  | 2013
ATC billings to WPL |  | $24 |  |  |  | $24 |
WPL billings to ATC | 3 |  |  | 3 |

X
- Definition Schedule of amounts billed for ATC (Table Text Block) + References No definition available. + Details
Name: | lnt_ScheduleOfAtcBillingsTableTextBlock
Namespace Prefix: | lnt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of Corporate Services Intercompany Payables (Table Text Block). + References No definition available. + Details
Name: | lnt_ScheduleOfCorporateServicesIntercompanyPayablesTableTextBlock
Namespace Prefix: | lnt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of System Coordination and Operating Agreement Schedule of Sales Credited and Purchases Billed (Table Text Block) + References No definition available. + Details
Name: | lnt_ScheduleOfScoaSalesCreditedAndPurchasesBilledTableTextBlock
Namespace Prefix: | lnt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration