v2.4.0.6

Segments Of Business

9 Months Ended

Sep. 30, 2012

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. As of September 30, 2012, Alliant Energy’s RMT business qualified as assets and liabilities held for sale. The operating results of RMT have been separately classified and reported as discontinued operations in Alliant Energy’s Condensed Consolidated Statements of Income. As a result, Alliant Energy no longer reports “Non-regulated - RMT” segment information. 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 September 30, 2012
Operating revenues		$815.3				$46.8				$12.2				$874.3				$13.3				$887.6
Operating income	203.1				0.8				1.5				205.4				8.3				213.7
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													159.2				(10.2		)		149.0
Income from discontinued operations, net of tax													—				1.7				1.7
Net income (loss) attributable to Alliant Energy common shareowners													159.2				(8.5		)		150.7
Three Months Ended September 30, 2011
Operating revenues		$796.9				$46.4				$15.8				$859.1				$11.8				$870.9
Operating income (loss)	206.1				(2.8		)		0.1				203.4				6.0				209.4
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													148.9				(12.0		)		136.9
Loss from discontinued operations, net of tax													—				(14.9		)		(14.9		)
Net income (loss) attributable to Alliant Energy common shareowners													148.9				(26.9		)		122.0

	Utility																Non-Regulated,				Alliant Energy
	Electric				Gas				Other				Total				Parent and Other				Consolidated
	(in millions)
Nine Months Ended September 30, 2012
Operating revenues		$2,000.3				$263.9				$39.7				$2,303.9				$39.7				$2,343.6
Operating income	354.0				32.1				4.7				390.8				27.3				418.1
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													237.4				16.4				253.8
Loss from discontinued operations, net of tax													—				(2.3		)		(2.3		)
Net income attributable to Alliant Energy common shareowners													237.4				14.1				251.5
Nine Months Ended September 30, 2011
Operating revenues		$2,037.7				$342.5				$45.8				$2,426.0				$34.6				$2,460.6
Operating income (loss)	357.6				34.0				(2.3		)		389.3				18.0				407.3
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													236.0				23.2				259.2
Loss from discontinued operations, net of tax													—				(12.6		)		(12.6		)
Net income attributable to Alliant Energy common shareowners													236.0				10.6				246.6

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 September 30, 2012
Operating revenues		$456.6				$29.6				$11.5				$497.7
Operating income	109.5				0.6				1.9				112.0
Earnings available for common stock													103.3
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$1,070.7				$149.2				$37.2				$1,257.1
Operating income	149.3				15.6				6.4				171.3
Earnings available for common stock													115.2
Nine Months Ended September 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

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 September 30, 2012
Operating revenues		$358.7				$17.2				$0.7				$376.6
Operating income	93.6				0.2				(0.4		)		93.4
Earnings available for common stock													55.9
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$929.6				$114.7				$2.5				$1,046.8
Operating income (loss)	204.7				16.5				(1.7		)		219.5
Earnings available for common stock													122.2
Nine Months Ended September 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

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. As of September 30, 2012, Alliant Energy’s RMT business qualified as assets and liabilities held for sale. The operating results of RMT have been separately classified and reported as discontinued operations in Alliant Energy’s Condensed Consolidated Statements of Income. As a result, Alliant Energy no longer reports “Non-regulated - RMT” segment information. 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 September 30, 2012
Operating revenues		$815.3				$46.8				$12.2				$874.3				$13.3				$887.6
Operating income	203.1				0.8				1.5				205.4				8.3				213.7
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													159.2				(10.2		)		149.0
Income from discontinued operations, net of tax													—				1.7				1.7
Net income (loss) attributable to Alliant Energy common shareowners													159.2				(8.5		)		150.7
Three Months Ended September 30, 2011
Operating revenues		$796.9				$46.4				$15.8				$859.1				$11.8				$870.9
Operating income (loss)	206.1				(2.8		)		0.1				203.4				6.0				209.4
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													148.9				(12.0		)		136.9
Loss from discontinued operations, net of tax													—				(14.9		)		(14.9		)
Net income (loss) attributable to Alliant Energy common shareowners													148.9				(26.9		)		122.0

	Utility																Non-Regulated,				Alliant Energy
	Electric				Gas				Other				Total				Parent and Other				Consolidated
	(in millions)
Nine Months Ended September 30, 2012
Operating revenues		$2,000.3				$263.9				$39.7				$2,303.9				$39.7				$2,343.6
Operating income	354.0				32.1				4.7				390.8				27.3				418.1
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													237.4				16.4				253.8
Loss from discontinued operations, net of tax													—				(2.3		)		(2.3		)
Net income attributable to Alliant Energy common shareowners													237.4				14.1				251.5
Nine Months Ended September 30, 2011
Operating revenues		$2,037.7				$342.5				$45.8				$2,426.0				$34.6				$2,460.6
Operating income (loss)	357.6				34.0				(2.3		)		389.3				18.0				407.3
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													236.0				23.2				259.2
Loss from discontinued operations, net of tax													—				(12.6		)		(12.6		)
Net income attributable to Alliant Energy common shareowners													236.0				10.6				246.6

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 September 30, 2012
Operating revenues		$456.6				$29.6				$11.5				$497.7
Operating income	109.5				0.6				1.9				112.0
Earnings available for common stock													103.3
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$1,070.7				$149.2				$37.2				$1,257.1
Operating income	149.3				15.6				6.4				171.3
Earnings available for common stock													115.2
Nine Months Ended September 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

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 September 30, 2012
Operating revenues		$358.7				$17.2				$0.7				$376.6
Operating income	93.6				0.2				(0.4		)		93.4
Earnings available for common stock													55.9
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$929.6				$114.7				$2.5				$1,046.8
Operating income (loss)	204.7				16.5				(1.7		)		219.5
Earnings available for common stock													122.2
Nine Months Ended September 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

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. As of September 30, 2012, Alliant Energy’s RMT business qualified as assets and liabilities held for sale. The operating results of RMT have been separately classified and reported as discontinued operations in Alliant Energy’s Condensed Consolidated Statements of Income. As a result, Alliant Energy no longer reports “Non-regulated - RMT” segment information. 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 September 30, 2012
Operating revenues		$815.3				$46.8				$12.2				$874.3				$13.3				$887.6
Operating income	203.1				0.8				1.5				205.4				8.3				213.7
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													159.2				(10.2		)		149.0
Income from discontinued operations, net of tax													—				1.7				1.7
Net income (loss) attributable to Alliant Energy common shareowners													159.2				(8.5		)		150.7
Three Months Ended September 30, 2011
Operating revenues		$796.9				$46.4				$15.8				$859.1				$11.8				$870.9
Operating income (loss)	206.1				(2.8		)		0.1				203.4				6.0				209.4
Amounts attributable to Alliant Energy common shareowners:
Income (loss) from continuing operations, net of tax													148.9				(12.0		)		136.9
Loss from discontinued operations, net of tax													—				(14.9		)		(14.9		)
Net income (loss) attributable to Alliant Energy common shareowners													148.9				(26.9		)		122.0

	Utility																Non-Regulated,				Alliant Energy
	Electric				Gas				Other				Total				Parent and Other				Consolidated
	(in millions)
Nine Months Ended September 30, 2012
Operating revenues		$2,000.3				$263.9				$39.7				$2,303.9				$39.7				$2,343.6
Operating income	354.0				32.1				4.7				390.8				27.3				418.1
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													237.4				16.4				253.8
Loss from discontinued operations, net of tax													—				(2.3		)		(2.3		)
Net income attributable to Alliant Energy common shareowners													237.4				14.1				251.5
Nine Months Ended September 30, 2011
Operating revenues		$2,037.7				$342.5				$45.8				$2,426.0				$34.6				$2,460.6
Operating income (loss)	357.6				34.0				(2.3		)		389.3				18.0				407.3
Amounts attributable to Alliant Energy common shareowners:
Income from continuing operations, net of tax													236.0				23.2				259.2
Loss from discontinued operations, net of tax													—				(12.6		)		(12.6		)
Net income attributable to Alliant Energy common shareowners													236.0				10.6				246.6

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 September 30, 2012
Operating revenues		$456.6				$29.6				$11.5				$497.7
Operating income	109.5				0.6				1.9				112.0
Earnings available for common stock													103.3
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$1,070.7				$149.2				$37.2				$1,257.1
Operating income	149.3				15.6				6.4				171.3
Earnings available for common stock													115.2
Nine Months Ended September 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

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 September 30, 2012
Operating revenues		$358.7				$17.2				$0.7				$376.6
Operating income	93.6				0.2				(0.4		)		93.4
Earnings available for common stock													55.9
Three Months Ended September 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
Nine Months Ended September 30, 2012
Operating revenues		$929.6				$114.7				$2.5				$1,046.8
Operating income (loss)	204.7				16.5				(1.7		)		219.5
Earnings available for common stock													122.2
Nine Months Ended September 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

X

- 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.

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