Related Parties (Tables)

9 Months Ended

Sep. 30, 2011

Related Parties

Sales Credited And Purchases Billed

	IPL								WPL
	Three Months				Nine Months				Three Months				Nine Months
	2011		2010		2011		2010		2011		2010		2011		2010
Sales credited	$	6.3	$	7.9	$	26.0	$	22.2	$	7.2	$	7.6	$	23.5	$	19.7
Purchases billed		93.0		88.2		238.4		263.0		20.1		17.4		56.4		60.5

Corporate Services Billings

	Three Months				Nine Months
	2011		2010		2011		2010
IPL	$	36.2	$	37.1	$	116.7	$	119.7
WPL		29.1		28.3		92.6		89.7

Net Intercompany Payables

	Sep. 30, 2011		Dec. 31, 2010
IPL	$	75.1	$	78.5
WPL		42.8		41.6

Amounts Billed Between Related Parties

	Three Months				Nine Months
	2011		2010		2011		2010
ATC billings to WPL	$	22.3	$	22.6	$	66.7	$	68.1
WPL billings to ATC		2.4		2.8		8.3		8.2