Segments Of Business

3 Months Ended

Mar. 31, 2013

Segment Reporting Information [Line Items]

SEGMENTS OF BUSINESS

Alliant Energy - 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 March 31, 2013
Operating revenues		$633.2		$197.3		$17.2		$847.7		$11.9			$859.6
Operating income	73.6		37.3		2.9		113.8		6.9			120.7
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							64.9		8.0			72.9
Loss from discontinued operations, net of tax							—		(3.0		)	(3.0		)
Net income attributable to Alliant Energy common shareowners							64.9		5.0			69.9
Three Months Ended March 31, 2012
Operating revenues		$572.4		$167.1		$13.7		$753.2		$12.5			$765.7
Operating income	59.1		27.7		1.7		88.5		7.1			95.6
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							26.4		12.9			39.3
Loss from discontinued operations, net of tax							—		(4.4		)	(4.4		)
Net income attributable to Alliant Energy common shareowners							26.4		8.5			34.9

IPL - 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 March 31, 2013
Operating revenues		$350.2		$114.3		$13.4		$477.9
Operating income	17.2		20.7		3.2		41.1
Earnings available for common stock							22.9
Three Months Ended March 31, 2012
Operating revenues		$293.1		$92.8		$12.8		$398.7
Operating income	6.7		14.2		3.0		23.9
Loss for common stock							(4.7		)

WPL - 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 March 31, 2013
Operating revenues		$283.0		$83.0		$3.8			$369.8
Operating income (loss)	56.4		16.6		(0.3		)	72.7
Earnings available for common stock								42.0
Three Months Ended March 31, 2012
Operating revenues		$279.3		$74.3		$0.9			$354.5
Operating income (loss)	52.4		13.5		(1.3		)	64.6
Earnings available for common stock								31.1

IPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Alliant Energy - 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 March 31, 2013
Operating revenues		$633.2		$197.3		$17.2		$847.7		$11.9			$859.6
Operating income	73.6		37.3		2.9		113.8		6.9			120.7
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							64.9		8.0			72.9
Loss from discontinued operations, net of tax							—		(3.0		)	(3.0		)
Net income attributable to Alliant Energy common shareowners							64.9		5.0			69.9
Three Months Ended March 31, 2012
Operating revenues		$572.4		$167.1		$13.7		$753.2		$12.5			$765.7
Operating income	59.1		27.7		1.7		88.5		7.1			95.6
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							26.4		12.9			39.3
Loss from discontinued operations, net of tax							—		(4.4		)	(4.4		)
Net income attributable to Alliant Energy common shareowners							26.4		8.5			34.9

IPL - 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 March 31, 2013
Operating revenues		$350.2		$114.3		$13.4		$477.9
Operating income	17.2		20.7		3.2		41.1
Earnings available for common stock							22.9
Three Months Ended March 31, 2012
Operating revenues		$293.1		$92.8		$12.8		$398.7
Operating income	6.7		14.2		3.0		23.9
Loss for common stock							(4.7		)

WPL - 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 March 31, 2013
Operating revenues		$283.0		$83.0		$3.8			$369.8
Operating income (loss)	56.4		16.6		(0.3		)	72.7
Earnings available for common stock								42.0
Three Months Ended March 31, 2012
Operating revenues		$279.3		$74.3		$0.9			$354.5
Operating income (loss)	52.4		13.5		(1.3		)	64.6
Earnings available for common stock								31.1

WPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Alliant Energy - 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 March 31, 2013
Operating revenues		$633.2		$197.3		$17.2		$847.7		$11.9			$859.6
Operating income	73.6		37.3		2.9		113.8		6.9			120.7
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							64.9		8.0			72.9
Loss from discontinued operations, net of tax							—		(3.0		)	(3.0		)
Net income attributable to Alliant Energy common shareowners							64.9		5.0			69.9
Three Months Ended March 31, 2012
Operating revenues		$572.4		$167.1		$13.7		$753.2		$12.5			$765.7
Operating income	59.1		27.7		1.7		88.5		7.1			95.6
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax							26.4		12.9			39.3
Loss from discontinued operations, net of tax							—		(4.4		)	(4.4		)
Net income attributable to Alliant Energy common shareowners							26.4		8.5			34.9

IPL - 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 March 31, 2013
Operating revenues		$350.2		$114.3		$13.4		$477.9
Operating income	17.2		20.7		3.2		41.1
Earnings available for common stock							22.9
Three Months Ended March 31, 2012
Operating revenues		$293.1		$92.8		$12.8		$398.7
Operating income	6.7		14.2		3.0		23.9
Loss for common stock							(4.7		)

WPL - 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 March 31, 2013
Operating revenues		$283.0		$83.0		$3.8			$369.8
Operating income (loss)	56.4		16.6		(0.3		)	72.7
Earnings available for common stock								42.0
Three Months Ended March 31, 2012
Operating revenues		$279.3		$74.3		$0.9			$354.5
Operating income (loss)	52.4		13.5		(1.3		)	64.6
Earnings available for common stock								31.1

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details