Commitments And Contingencies (Tables)

6 Months Ended

Jun. 30, 2014

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At June 30, 2014, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a):
DAEC (IPL)		$1,589		$1,589		$—
Other	235		1		234
	1,824		1,590		234
Natural gas	253		135		118
Coal (b)	279		123		156
SO2 emission allowances	34		34		—
Other (c)	33		20		10
		$2,423		$1,902		$518

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased.

(b) 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 June 30, 2014 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2014.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2014, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions):

	Alliant Energy				IPL				WPL
Range of estimated future costs		$13	-	$32		$12	-	$30		$1	-	$2
Current and non-current environmental liabilities	20				18				2

IPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At June 30, 2014, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a):
DAEC (IPL)		$1,589		$1,589		$—
Other	235		1		234
	1,824		1,590		234
Natural gas	253		135		118
Coal (b)	279		123		156
SO2 emission allowances	34		34		—
Other (c)	33		20		10
		$2,423		$1,902		$518

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased.

(b) 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 June 30, 2014 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2014.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2014, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions):

	Alliant Energy				IPL				WPL
Range of estimated future costs		$13	-	$32		$12	-	$30		$1	-	$2
Current and non-current environmental liabilities	20				18				2

WPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At June 30, 2014, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a):
DAEC (IPL)		$1,589		$1,589		$—
Other	235		1		234
	1,824		1,590		234
Natural gas	253		135		118
Coal (b)	279		123		156
SO2 emission allowances	34		34		—
Other (c)	33		20		10
		$2,423		$1,902		$518

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased.

(b) 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 June 30, 2014 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2014.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2014, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions):

	Alliant Energy				IPL				WPL
Range of estimated future costs		$13	-	$32		$12	-	$30		$1	-	$2
Current and non-current environmental liabilities	20				18				2