Related Parties

9 Months Ended

Sep. 30, 2012

Related Party Transaction [Line Items]

Related Parties

RELATED PARTIES

System Coordination and Operating Agreement - IPL and WPL are parties to a system coordination and operating agreement whereby Corporate Services serves as agent on behalf of IPL and WPL. The agreement, which has been approved or reviewed by FERC and all state regulatory bodies having jurisdiction, provides a contractual basis for coordinated planning, construction, operation and maintenance of the interconnected electric generation systems of IPL and WPL. As agent of the agreement, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions. Corporate Services allocates such sales and purchases among IPL and WPL based on procedures included in the agreement. 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

Service Agreement - Pursuant to a service agreement, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation, benefits and fees associated with various professional services. 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 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

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. 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

WPL owed ATC net amounts of $6 million as of September 30, 2012 and $6 million as of December 31, 2011.

IPL’s Sale of Certain Wind Project Assets to Resources - Pursuant to a wind development asset purchase and sale agreement, IPL sold Resources wind project assets for the Franklin County wind project at cost in the second quarter of 2011 for $115.3 million.

IPL [Member]

Related Party Transaction [Line Items]

Related Parties

RELATED PARTIES

System Coordination and Operating Agreement - IPL and WPL are parties to a system coordination and operating agreement whereby Corporate Services serves as agent on behalf of IPL and WPL. The agreement, which has been approved or reviewed by FERC and all state regulatory bodies having jurisdiction, provides a contractual basis for coordinated planning, construction, operation and maintenance of the interconnected electric generation systems of IPL and WPL. As agent of the agreement, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions. Corporate Services allocates such sales and purchases among IPL and WPL based on procedures included in the agreement. 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

Service Agreement - Pursuant to a service agreement, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation, benefits and fees associated with various professional services. 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 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

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. 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

WPL owed ATC net amounts of $6 million as of September 30, 2012 and $6 million as of December 31, 2011.

IPL’s Sale of Certain Wind Project Assets to Resources - Pursuant to a wind development asset purchase and sale agreement, IPL sold Resources wind project assets for the Franklin County wind project at cost in the second quarter of 2011 for $115.3 million.

WPL [Member]

Related Party Transaction [Line Items]

Related Parties

RELATED PARTIES

System Coordination and Operating Agreement - IPL and WPL are parties to a system coordination and operating agreement whereby Corporate Services serves as agent on behalf of IPL and WPL. The agreement, which has been approved or reviewed by FERC and all state regulatory bodies having jurisdiction, provides a contractual basis for coordinated planning, construction, operation and maintenance of the interconnected electric generation systems of IPL and WPL. As agent of the agreement, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions. Corporate Services allocates such sales and purchases among IPL and WPL based on procedures included in the agreement. 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

Service Agreement - Pursuant to a service agreement, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation, benefits and fees associated with various professional services. 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 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

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. 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

WPL owed ATC net amounts of $6 million as of September 30, 2012 and $6 million as of December 31, 2011.

IPL’s Sale of Certain Wind Project Assets to Resources - Pursuant to a wind development asset purchase and sale agreement, IPL sold Resources wind project assets for the Franklin County wind project at cost in the second quarter of 2011 for $115.3 million.