v2.4.0.6

Investments (Tables)

12 Months Ended

Dec. 31, 2012

Investment [Line Items]

Unconsolidated Equity Investments

Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting are as follows (in millions):

	Ownership		Carrying Value at
	Interest at		December 31,								Equity (Income) / Loss
	December 31, 2012		2012				2011				2012				2011				2010
Alliant Energy
ATC (a)	16%			$257.0				$238.8				($41.3	)			($37.8	)			($36.9	)
Wisconsin River Power Company	50%		7.3				7.7				(0.8		)		(0.9		)		(0.9		)
Other	Various		2.3				3.1				0.8				(0.6		)		(0.3		)
				$266.6				$249.6				($41.3	)			($39.3	)			($38.1	)
WPL
ATC (a)	16%			$257.0				$238.8				($41.3	)			($37.8	)			($36.9	)
Wisconsin River Power Company	50%		7.3				7.7				(0.8		)		(0.9		)		(0.9		)
				$264.3				$246.5				($42.1	)			($38.7	)			($37.8	)

(a) Alliant Energy and WPL have the ability to exercise significant influence over ATC’s financial and operating policies through their participation on ATC’s Board of Directors. Refer to Note 19 for information regarding related party transactions with ATC.

Summary Financial Information

Summary aggregate financial information from the financial statements of these investments is as follows (in millions):

	Alliant Energy												WPL
	2012				2011				2010				2012				2011				2010
Operating revenues		$611				$575				$564				$611				$575				$564
Operating income	326				307				307				325				308				308
Net income	234				218				226				239				226				221
As of December 31:
Current assets	67				62								66				61
Non-current assets	3,321				3,100								3,292				3,071
Current liabilities	252				299								252				299
Non-current liabilities	1,652				1,490								1,651				1,487

Cash Surrender Value of Life Insurance Policies

At December 31, the cash surrender value of these investments was as follows (in millions):

	Alliant Energy				IPL				WPL
	2012		2011		2012		2011		2012		2011
Cash surrender value	$50.5		$49.2		$16.0		$15.1		$12.1		$11.9

IPL [Member]

Investment [Line Items]

Cash Surrender Value of Life Insurance Policies

At December 31, the cash surrender value of these investments was as follows (in millions):

	Alliant Energy				IPL				WPL
	2012		2011		2012		2011		2012		2011
Cash surrender value	$50.5		$49.2		$16.0		$15.1		$12.1		$11.9

WPL [Member]

Investment [Line Items]

Unconsolidated Equity Investments

Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting are as follows (in millions):

	Ownership		Carrying Value at
	Interest at		December 31,								Equity (Income) / Loss
	December 31, 2012		2012				2011				2012				2011				2010
Alliant Energy
ATC (a)	16%			$257.0				$238.8				($41.3	)			($37.8	)			($36.9	)
Wisconsin River Power Company	50%		7.3				7.7				(0.8		)		(0.9		)		(0.9		)
Other	Various		2.3				3.1				0.8				(0.6		)		(0.3		)
				$266.6				$249.6				($41.3	)			($39.3	)			($38.1	)
WPL
ATC (a)	16%			$257.0				$238.8				($41.3	)			($37.8	)			($36.9	)
Wisconsin River Power Company	50%		7.3				7.7				(0.8		)		(0.9		)		(0.9		)
				$264.3				$246.5				($42.1	)			($38.7	)			($37.8	)

(a) Alliant Energy and WPL have the ability to exercise significant influence over ATC’s financial and operating policies through their participation on ATC’s Board of Directors. Refer to Note 19 for information regarding related party transactions with ATC.

Summary Financial Information

Summary aggregate financial information from the financial statements of these investments is as follows (in millions):

	Alliant Energy												WPL
	2012				2011				2010				2012				2011				2010
Operating revenues		$611				$575				$564				$611				$575				$564
Operating income	326				307				307				325				308				308
Net income	234				218				226				239				226				221
As of December 31:
Current assets	67				62								66				61
Non-current assets	3,321				3,100								3,292				3,071
Current liabilities	252				299								252				299
Non-current liabilities	1,652				1,490								1,651				1,487

Cash Surrender Value of Life Insurance Policies

At December 31, the cash surrender value of these investments was as follows (in millions):

	Alliant Energy				IPL				WPL
	2012		2011		2012		2011		2012		2011
Cash surrender value	$50.5		$49.2		$16.0		$15.1		$12.1		$11.9

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Tabular disclosure of equity method investments in common stock. The disclosure may include: (a) the name of each investee or group of investments for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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