Investments (Tables)

9 Months Ended

Sep. 30, 2013

Schedule of Investments [Line Items]

Unconsolidated Equity Investments

Equity (income) loss from Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting for the three and nine months ended September 30 was as follows (in millions):

	Alliant Energy												WPL
	Three Months						Nine Months						Three Months						Nine Months
	2013			2012			2013			2012			2013			2012			2013			2012
ATC		($10.8	)		($10.4	)		($31.7	)		($30.6	)		($10.8	)		($10.4	)		($31.7	)		($30.6	)
Other	(0.3		)	—			(1.0		)	0.2			(0.3		)	(0.1		)	(1.0		)	(0.6		)
		($11.1	)		($10.4	)		($32.7	)		($30.4	)		($11.1	)		($10.5	)		($32.7	)		($31.2	)

Summary Financial Information

Summary financial information from the unaudited financial statements of ATC for the three and nine months ended September 30 was as follows (in millions):

	Three Months				Nine Months
	2013		2012		2013		2012
Operating revenues		$160.4		$150.3		$464.3		$450.1
Operating income	82.9		81.5		247.1		240.0
Net income	62.7		60.5		184.5		177.9

WPL [Member]

Schedule of Investments [Line Items]

Unconsolidated Equity Investments

Equity (income) loss from Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting for the three and nine months ended September 30 was as follows (in millions):

	Alliant Energy												WPL
	Three Months						Nine Months						Three Months						Nine Months
	2013			2012			2013			2012			2013			2012			2013			2012
ATC		($10.8	)		($10.4	)		($31.7	)		($30.6	)		($10.8	)		($10.4	)		($31.7	)		($30.6	)
Other	(0.3		)	—			(1.0		)	0.2			(0.3		)	(0.1		)	(1.0		)	(0.6		)
		($11.1	)		($10.4	)		($32.7	)		($30.4	)		($11.1	)		($10.5	)		($32.7	)		($31.2	)

Summary Financial Information

Summary financial information from the unaudited financial statements of ATC for the three and nine months ended September 30 was as follows (in millions):

	Three Months				Nine Months
	2013		2012		2013		2012
Operating revenues		$160.4		$150.3		$464.3		$450.1
Operating income	82.9		81.5		247.1		240.0
Net income	62.7		60.5		184.5		177.9