Segments Of Business (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations.

	Utility								Non-Regulated,			Alliant Energy
	Electric		Gas		Other		Total		Parent and Other			Consolidated
	(in millions)
Three Months Ended June 30, 2013
Operating revenues		$612.1		$73.4		$17.8		$703.3		$14.7			$718.0
Operating income	85.9		5.6		2.9		94.4		8.8			103.2
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							56.6		9.3			65.9
Loss from discontinued operations, net of tax							—		(0.6		)	(0.6		)
Net income attributable to Alliant Energy common shareowners							56.6		8.7			65.3
Three Months Ended June 30, 2012
Operating revenues		$612.6		$50.0		$13.8		$676.4		$13.9			$690.3
Operating income	91.8		3.6		1.5		96.9		11.9			108.8
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							51.8		13.7			65.5
Income from discontinued operations, net of tax							—		0.4			0.4
Net income attributable to Alliant Energy common shareowners							51.8		14.1			65.9

	Utility								Non-Regulated,			Alliant Energy
	Electric		Gas		Other		Total		Parent and Other			Consolidated
	(in millions)
Six Months Ended June 30, 2013
Operating revenues		$1,245.3		$270.7		$35.0		$1,551.0		$26.6			$1,577.6
Operating income	159.5		42.9		5.8		208.2		15.7			223.9
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							121.5		17.3			138.8
Loss from discontinued operations, net of tax							—		(3.6		)	(3.6		)
Net income attributable to Alliant Energy common shareowners							121.5		13.7			135.2
Six Months Ended June 30, 2012
Operating revenues		$1,185.0		$217.1		$27.5		$1,429.6		$26.4			$1,456.0
Operating income	150.9		31.3		3.2		185.4		19.0			204.4
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							78.2		26.6			104.8
Loss from discontinued operations, net of tax							—		(4.0		)	(4.0		)
Net income attributable to Alliant Energy common shareowners							78.2		22.6			100.8

IPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations.

	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2013
Operating revenues		$329.6		$42.0		$11.8		$383.4
Operating income	29.4		2.6		2.7		34.7
Earnings available for common stock							22.2
Three Months Ended June 30, 2012
Operating revenues		$321.0		$26.8		$12.9		$360.7
Operating income	33.1		0.8		1.5		35.4
Earnings available for common stock							16.6
Six Months Ended June 30, 2013
Operating revenues		$679.8		$156.3		$25.2		$861.3
Operating income	46.6		23.3		5.9		75.8
Earnings available for common stock							45.1
Six Months Ended June 30, 2012
Operating revenues		$614.1		$119.6		$25.7		$759.4
Operating income	39.8		15.0		4.5		59.3
Earnings available for common stock							11.9

WPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations.

	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2013
Operating revenues		$282.5		$31.4		$6.0			$319.9
Operating income	56.5		3.0		0.2			59.7
Earnings available for common stock								34.4
Three Months Ended June 30, 2012
Operating revenues		$291.6		$23.2		$0.9			$315.7
Operating income	58.7		2.8		—			61.5
Earnings available for common stock								35.2
Six Months Ended June 30, 2013
Operating revenues		$565.5		$114.4		$9.8			$689.7
Operating income (loss)	112.9		19.6		(0.1		)	132.4
Earnings available for common stock								76.4
Six Months Ended June 30, 2012
Operating revenues		$570.9		$97.5		$1.8			$670.2
Operating income (loss)	111.1		16.3		(1.3		)	126.1
Earnings available for common stock								66.3