Segments Of Business (Tables)

9 Months Ended

Sep. 30, 2011

Alliant Energy Corporation [Member]

Segments Of Business

	Utility										Non-regulated, Parent and Other						Alliant Energy
	Electric		Gas			Other			Total		RMT			Other			Consolidated
	(in millions)
Three Months Ended Sep. 30, 2011
Operating revenues	$	796.9	$	46.4		$	15.8		$	859.1	$	150.7		$	11.8		$	1,021.6
Operating income (loss)		206.1		(2.8	)		0.1			203.4		(24.3	)		6.0			185.1
Net income (loss) attributable to Alliant Energy common shareowners										148.9		(14.9	)		(12.0	)		122.0
Three Months Ended Sep. 30, 2010
Operating revenues		842.0		46.5			15.9			904.4		35.9			11.4			951.7
Operating income (loss)		241.1		(2.9	)		4.2			242.4		(1.0	)		5.2			246.6
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax										146.0		(0.6	)		5.5			150.9
Loss from discontinued operations, net of tax										—		—			(1.8	)		(1.8	)
Net income (loss) attributable to Alliant Energy common shareowners										146.0		(0.6	)		3.7			149.1
	Utility										Non-regulated, Parent and Other						Alliant Energy
	Electric		Gas			Other			Total		RMT			Other			Consolidated
	(in millions)
Nine Months Ended Sep. 30, 2011
Operating revenues	$	2,037.7	$	342.5		$	45.8		$	2,426.0	$	325.5		$	34.6		$	2,786.1
Operating income (loss)		357.6		34.0			(2.3	)		389.3		(22.4	)		18.0			384.9
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax										236.0		(13.9	)		23.2			245.3
Income from discontinued operations, net of tax										—		—			1.3			1.3
Net income (loss) attributable to Alliant Energy common shareowners										236.0		(13.9	)		24.5			246.6
Nine Months Ended Sep. 30, 2010
Operating revenues		2,074.2		330.9			48.9			2,454.0		97.9			31.6			2,583.5
Operating income (loss)		408.3		33.8			5.8			447.9		(4.7	)		13.1			456.3
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax										234.7		(2.9	)		10.5			242.3
Loss from discontinued operations, net of tax										—		—			(2.0	)		(2.0	)
Net income (loss) attributable to Alliant Energy common shareowners										234.7		(2.9	)		8.5			240.3

IPL [Member]

Segments Of Business

	Electric		Gas			Other		Total
	(in millions)
Three Months Ended Sep. 30, 2011
Operating revenues	$	443.2	$	27.5		$	13.8	$	484.5
Operating income (loss)		117.5		(1.3	)		0.3		116.5
Earnings available for common stock									98.3
Three Months Ended Sep. 30, 2010
Operating revenues		492.4		28.1			14.3		534.8
Operating income (loss)		151.9		(0.7	)		4.5		155.7
Earnings available for common stock									96.8
Nine Months Ended Sep. 30, 2011
Operating revenues		1,097.3		198.1			40.7		1,336.1
Operating income		162.3		15.1			4.7		182.1
Earnings available for common stock									117.7
Nine Months Ended Sep. 30, 2010
Operating revenues		1,146.8		187.9			43.9		1,378.6
Operating income		213.7		18.1			7.4		239.2
Earnings available for common stock									120.0

WPL [Member]

Segments Of Business

	Electric		Gas			Other			Total
	(in millions)
Three Months Ended Sep. 30, 2011
Operating revenues	$	353.7	$	18.9		$	2.0		$	374.6
Operating income (loss)		88.6		(1.5	)		(0.2	)		86.9
Earnings available for common stock										50.6
Three Months Ended Sep. 30, 2010
Operating revenues		349.6		18.4			1.6			369.6
Operating income (loss)		89.2		(2.2	)		(0.3	)		86.7
Earnings available for common stock										49.2
Nine Months Ended Sep. 30, 2011
Operating revenues		940.4		144.4			5.1			1,089.9
Operating income (loss)		195.3		18.9			(7.0	)		207.2
Earnings available for common stock										118.3
Nine Months Ended Sep. 30, 2010
Operating revenues		927.4		143.0			5.0			1,075.4
Operating income (loss)		194.6		15.7			(1.6	)		208.7
Earnings available for common stock										114.7