Commitments And Contingencies (Tables)

12 Months Ended

Dec. 31, 2013

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2013, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (IPL) (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	52		73		45		44		44		—		258
	172		192		172		182		172		1,025		1,915
Natural gas	187		65		34		10		2		6		304
Coal (c)	128		81		59		30		21		—		319
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	8		3		—		—		—		—		11
		$495		$353		$279		$230		$195		$1,031		$2,583

IPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	—		—		1		—		—		—		1
	120		119		128		138		128		1,025		1,658
Natural gas	129		37		15		3		1		6		191
Coal (c)	63		32		27		11		6		—		139
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	5		1		—		—		—		—		6
	$317			$201		$184		$160		$135		$1,031		$2,028

WPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a)		$52		$73		$44		$44		$44		$—		$257
Natural gas	58		28		19		7		1		—		113
Coal (c)	65		49		32		19		15		—		180
Other (e)	2		—		—		—		—		—		2
		$177		$150		$95		$70		$60		$—		$552

(a) Includes payments required by PPAs for capacity rights (Alliant Energy and IPL only) and minimum quantities of MWhs required to be purchased. Refer to Note 18 for additional information on purchased power transactions.

(b) Includes commitments incurred under an existing PPA that expires February 2014 and a new PPA effective February 2014. The new PPA grants IPL rights to purchase 431 MWs of capacity and the resulting energy from DAEC for a term from the expiration of the existing PPA in February 2014 through December 31, 2025. If energy delivered under the new PPA is less than the targeted energy amount, an adjustment payment will be made to IPL, which will be reflected in IPL’s fuel adjustment clause.

(c) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of December 31, 2013 regarding expected future usage, which is subject to change.

(d) Refer to Note 2 for discussion of $34 million of charges recognized by Alliant Energy and IPL in 2011 for forward contracts to purchase SO2 emission allowances.

(e) Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2013.

Schedule of Environmental Liabilities

At December 31, current environmental liabilities were included in “Other current liabilities” and non-current environmental liabilities were included in “Other long-term liabilities and deferred credits” on the Consolidated Balance Sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	2013		2012		2013		2012		2013		2012
Current environmental liabilities		$3.6		$3.7		$2.8		$2.5		$0.8		$1.2
Non-current environmental liabilities	15.4		25.3		13.6		23.2		1.7		2.1
		$19.0		$29.0		$16.4		$25.7		$2.5		$3.3

IPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2013, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (IPL) (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	52		73		45		44		44		—		258
	172		192		172		182		172		1,025		1,915
Natural gas	187		65		34		10		2		6		304
Coal (c)	128		81		59		30		21		—		319
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	8		3		—		—		—		—		11
		$495		$353		$279		$230		$195		$1,031		$2,583

IPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	—		—		1		—		—		—		1
	120		119		128		138		128		1,025		1,658
Natural gas	129		37		15		3		1		6		191
Coal (c)	63		32		27		11		6		—		139
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	5		1		—		—		—		—		6
	$317			$201		$184		$160		$135		$1,031		$2,028

WPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a)		$52		$73		$44		$44		$44		$—		$257
Natural gas	58		28		19		7		1		—		113
Coal (c)	65		49		32		19		15		—		180
Other (e)	2		—		—		—		—		—		2
		$177		$150		$95		$70		$60		$—		$552

(a) Includes payments required by PPAs for capacity rights (Alliant Energy and IPL only) and minimum quantities of MWhs required to be purchased. Refer to Note 18 for additional information on purchased power transactions.

(b) Includes commitments incurred under an existing PPA that expires February 2014 and a new PPA effective February 2014. The new PPA grants IPL rights to purchase 431 MWs of capacity and the resulting energy from DAEC for a term from the expiration of the existing PPA in February 2014 through December 31, 2025. If energy delivered under the new PPA is less than the targeted energy amount, an adjustment payment will be made to IPL, which will be reflected in IPL’s fuel adjustment clause.

(c) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of December 31, 2013 regarding expected future usage, which is subject to change.

(d) Refer to Note 2 for discussion of $34 million of charges recognized by Alliant Energy and IPL in 2011 for forward contracts to purchase SO2 emission allowances.

(e) Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2013.

Schedule of Environmental Liabilities

At December 31, current environmental liabilities were included in “Other current liabilities” and non-current environmental liabilities were included in “Other long-term liabilities and deferred credits” on the Consolidated Balance Sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	2013		2012		2013		2012		2013		2012
Current environmental liabilities		$3.6		$3.7		$2.8		$2.5		$0.8		$1.2
Non-current environmental liabilities	15.4		25.3		13.6		23.2		1.7		2.1
		$19.0		$29.0		$16.4		$25.7		$2.5		$3.3

WPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2013, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (IPL) (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	52		73		45		44		44		—		258
	172		192		172		182		172		1,025		1,915
Natural gas	187		65		34		10		2		6		304
Coal (c)	128		81		59		30		21		—		319
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	8		3		—		—		—		—		11
		$495		$353		$279		$230		$195		$1,031		$2,583

IPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a):
DAEC (b)		$120		$119		$127		$138		$128		$1,025		$1,657
Other	—		—		1		—		—		—		1
	120		119		128		138		128		1,025		1,658
Natural gas	129		37		15		3		1		6		191
Coal (c)	63		32		27		11		6		—		139
SO2 emission allowances (d)	—		12		14		8		—		—		34
Other (e)	5		1		—		—		—		—		6
	$317			$201		$184		$160		$135		$1,031		$2,028

WPL	2014		2015		2016		2017		2018		Thereafter		Total
Purchased power (a)		$52		$73		$44		$44		$44		$—		$257
Natural gas	58		28		19		7		1		—		113
Coal (c)	65		49		32		19		15		—		180
Other (e)	2		—		—		—		—		—		2
		$177		$150		$95		$70		$60		$—		$552

(a) Includes payments required by PPAs for capacity rights (Alliant Energy and IPL only) and minimum quantities of MWhs required to be purchased. Refer to Note 18 for additional information on purchased power transactions.

(b) Includes commitments incurred under an existing PPA that expires February 2014 and a new PPA effective February 2014. The new PPA grants IPL rights to purchase 431 MWs of capacity and the resulting energy from DAEC for a term from the expiration of the existing PPA in February 2014 through December 31, 2025. If energy delivered under the new PPA is less than the targeted energy amount, an adjustment payment will be made to IPL, which will be reflected in IPL’s fuel adjustment clause.

(c) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of December 31, 2013 regarding expected future usage, which is subject to change.

(d) Refer to Note 2 for discussion of $34 million of charges recognized by Alliant Energy and IPL in 2011 for forward contracts to purchase SO2 emission allowances.

(e) Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2013.

Schedule of Environmental Liabilities

At December 31, current environmental liabilities were included in “Other current liabilities” and non-current environmental liabilities were included in “Other long-term liabilities and deferred credits” on the Consolidated Balance Sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	2013		2012		2013		2012		2013		2012
Current environmental liabilities		$3.6		$3.7		$2.8		$2.5		$0.8		$1.2
Non-current environmental liabilities	15.4		25.3		13.6		23.2		1.7		2.1
		$19.0		$29.0		$16.4		$25.7		$2.5		$3.3