v2.4.0.6

Commitments And Contingencies (Tables)

12 Months Ended

Dec. 31, 2012

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2012, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (IPL) (b)		$200				$34				$—				$—				$—				$—				$234
Kewaunee Nuclear Power Plant (Kewaunee) (WPL)	77				—				—				—				—				—				77
Other	8				14				30				—				—				—				52
	285				48				30				—				—				—				363
Natural gas	163				55				37				21				10				6				292
Coal (c)	126				80				44				10				4				—				264
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	22				4				3				—				—				—				29
		$596				$187				$126				$45				$22				$6				$982

IPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (b)		$200				$34				$—				$—				$—				$—				$234
Other	1				—				—				—				—				—				1
	201				34				—				—				—				—				235
Natural gas	109				29				21				8				3				6				176
Coal (c)	36				28				11				5				—				—				80
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	9				2				1				—				—				—				12
		$355				$93				$45				$27				$11				$6				$537

WPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
Kewaunee		$77				$—				$—				$—				$—				$—				$77
Other	7				14				30				—				—				—				51
	84				14				30				—				—				—				128
Natural gas	54				26				16				13				7				—				116
Coal (c)	19				18				11				—				—				—				48
Other (e)	11				—				—				—				—				—				11
		$168				$58				$57				$13				$7				$—				$303

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. Refer to Note 19 for additional information on purchased power transactions.

(b) IPL is obligated to pay for capacity and energy delivered under the DAEC PPA. If energy delivered under the DAEC PPA is less than the targeted energy amount, an adjustment payment is made to IPL, which is reflected in IPL’s energy adjustment clause. In January 2013, the IUB issued an order approving a proposed DAEC PPA, with 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. As of December 31, 2012, there was no minimum future commitment for the proposed DAEC PPA.

(c) IPL and WPL entered into coal contracts (directly assigned to certain generating stations) and coal transportation contracts (directly assigned to corresponding transloading terminals), the amounts of which are included in each of the tables above. Also included in Alliant Energy’s and IPL’s tables is IPL’s respective portion of coal and coal transportation contracts related to jointly-owned generating stations not operated by IPL. In addition, Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL of $71 million, $34 million, $22 million, $5 million and $4 million for 2013, 2014, 2015, 2016 and 2017, respectively, to allow flexibility for the changing needs of the quantity of coal consumed by each. Coal contract quantities are allocated to specific IPL or WPL generating stations at or before the time of delivery based on various factors including projected heat input requirements, combustion compatibility and efficiency. These system-wide coal contracts have not been directly assigned to IPL and WPL since the specific needs of each utility were not yet known as of December 31, 2012 and therefore are excluded from IPL’s and WPL’s tables above.

(d) Refer to Note 1(b) 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, 2012.

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
	2012				2011				2012				2011				2012				2011
Current environmental liabilities		$3.7				$4.8				$2.5				$3.5				$1.2				$1.3
Non-current environmental liabilities	25.3				28.8				23.2				24.9				2.1				3.8
		$29.0				$33.6				$25.7				$28.4				$3.3				$5.1

IPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2012, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (IPL) (b)		$200				$34				$—				$—				$—				$—				$234
Kewaunee Nuclear Power Plant (Kewaunee) (WPL)	77				—				—				—				—				—				77
Other	8				14				30				—				—				—				52
	285				48				30				—				—				—				363
Natural gas	163				55				37				21				10				6				292
Coal (c)	126				80				44				10				4				—				264
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	22				4				3				—				—				—				29
		$596				$187				$126				$45				$22				$6				$982

IPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (b)		$200				$34				$—				$—				$—				$—				$234
Other	1				—				—				—				—				—				1
	201				34				—				—				—				—				235
Natural gas	109				29				21				8				3				6				176
Coal (c)	36				28				11				5				—				—				80
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	9				2				1				—				—				—				12
		$355				$93				$45				$27				$11				$6				$537

WPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
Kewaunee		$77				$—				$—				$—				$—				$—				$77
Other	7				14				30				—				—				—				51
	84				14				30				—				—				—				128
Natural gas	54				26				16				13				7				—				116
Coal (c)	19				18				11				—				—				—				48
Other (e)	11				—				—				—				—				—				11
		$168				$58				$57				$13				$7				$—				$303

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. Refer to Note 19 for additional information on purchased power transactions.

(b) IPL is obligated to pay for capacity and energy delivered under the DAEC PPA. If energy delivered under the DAEC PPA is less than the targeted energy amount, an adjustment payment is made to IPL, which is reflected in IPL’s energy adjustment clause. In January 2013, the IUB issued an order approving a proposed DAEC PPA, with 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. As of December 31, 2012, there was no minimum future commitment for the proposed DAEC PPA.

(c) IPL and WPL entered into coal contracts (directly assigned to certain generating stations) and coal transportation contracts (directly assigned to corresponding transloading terminals), the amounts of which are included in each of the tables above. Also included in Alliant Energy’s and IPL’s tables is IPL’s respective portion of coal and coal transportation contracts related to jointly-owned generating stations not operated by IPL. In addition, Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL of $71 million, $34 million, $22 million, $5 million and $4 million for 2013, 2014, 2015, 2016 and 2017, respectively, to allow flexibility for the changing needs of the quantity of coal consumed by each. Coal contract quantities are allocated to specific IPL or WPL generating stations at or before the time of delivery based on various factors including projected heat input requirements, combustion compatibility and efficiency. These system-wide coal contracts have not been directly assigned to IPL and WPL since the specific needs of each utility were not yet known as of December 31, 2012 and therefore are excluded from IPL’s and WPL’s tables above.

(d) Refer to Note 1(b) 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, 2012.

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
	2012				2011				2012				2011				2012				2011
Current environmental liabilities		$3.7				$4.8				$2.5				$3.5				$1.2				$1.3
Non-current environmental liabilities	25.3				28.8				23.2				24.9				2.1				3.8
		$29.0				$33.6				$25.7				$28.4				$3.3				$5.1

WPL [Member]

Long-term Purchase Commitment [Line Items]

Operating Expense Purchase Obligations

At December 31, 2012, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

Alliant Energy	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (IPL) (b)		$200				$34				$—				$—				$—				$—				$234
Kewaunee Nuclear Power Plant (Kewaunee) (WPL)	77				—				—				—				—				—				77
Other	8				14				30				—				—				—				52
	285				48				30				—				—				—				363
Natural gas	163				55				37				21				10				6				292
Coal (c)	126				80				44				10				4				—				264
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	22				4				3				—				—				—				29
		$596				$187				$126				$45				$22				$6				$982

IPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
DAEC (b)		$200				$34				$—				$—				$—				$—				$234
Other	1				—				—				—				—				—				1
	201				34				—				—				—				—				235
Natural gas	109				29				21				8				3				6				176
Coal (c)	36				28				11				5				—				—				80
SO2 emission allowances (d)	—				—				12				14				8				—				34
Other (e)	9				2				1				—				—				—				12
		$355				$93				$45				$27				$11				$6				$537

WPL	2013				2014				2015				2016				2017				Thereafter				Total
Purchased power (a):
Kewaunee		$77				$—				$—				$—				$—				$—				$77
Other	7				14				30				—				—				—				51
	84				14				30				—				—				—				128
Natural gas	54				26				16				13				7				—				116
Coal (c)	19				18				11				—				—				—				48
Other (e)	11				—				—				—				—				—				11
		$168				$58				$57				$13				$7				$—				$303

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. Refer to Note 19 for additional information on purchased power transactions.

(b) IPL is obligated to pay for capacity and energy delivered under the DAEC PPA. If energy delivered under the DAEC PPA is less than the targeted energy amount, an adjustment payment is made to IPL, which is reflected in IPL’s energy adjustment clause. In January 2013, the IUB issued an order approving a proposed DAEC PPA, with 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. As of December 31, 2012, there was no minimum future commitment for the proposed DAEC PPA.

(c) IPL and WPL entered into coal contracts (directly assigned to certain generating stations) and coal transportation contracts (directly assigned to corresponding transloading terminals), the amounts of which are included in each of the tables above. Also included in Alliant Energy’s and IPL’s tables is IPL’s respective portion of coal and coal transportation contracts related to jointly-owned generating stations not operated by IPL. In addition, Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL of $71 million, $34 million, $22 million, $5 million and $4 million for 2013, 2014, 2015, 2016 and 2017, respectively, to allow flexibility for the changing needs of the quantity of coal consumed by each. Coal contract quantities are allocated to specific IPL or WPL generating stations at or before the time of delivery based on various factors including projected heat input requirements, combustion compatibility and efficiency. These system-wide coal contracts have not been directly assigned to IPL and WPL since the specific needs of each utility were not yet known as of December 31, 2012 and therefore are excluded from IPL’s and WPL’s tables above.

(d) Refer to Note 1(b) 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, 2012.

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
	2012				2011				2012				2011				2012				2011
Current environmental liabilities		$3.7				$4.8				$2.5				$3.5				$1.2				$1.3
Non-current environmental liabilities	25.3				28.8				23.2				24.9				2.1				3.8
		$29.0				$33.6				$25.7				$28.4				$3.3				$5.1

X

- Definition

Tabular disclosure of material liabilities for remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal or abandonment of a property as a result of unanticipated contamination of the assets.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q4)

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Tabular disclosure of unconditional purchase obligations that are not recognized as a liability on the balance sheet, including the nature and significant terms of an unconditional purchase obligation; the amount of the fixed and determinable portion of the obligation as of the date of the latest balance sheet presented in the aggregate and, if determinable, for each of the five succeeding fiscal years; the nature of any variable components of the obligation; the amount purchased under the obligation (for example, the take-or-pay or throughput contract) for the reporting period; and may include the amount of imputed interest necessary to reduce the obligation to present value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 8

-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.



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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 7

-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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