Derivative Instruments (Tables)

9 Months Ended

Sep. 30, 2014

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of September 30, 2014, gross notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	2014	2015	2016	2017	2018	Total
Alliant Energy
Electricity (MWhs)	2,092	3,946	1,553	1,314	1,314	10,219
FTRs (MWhs)	5,673	9,560	—	—	—	15,233
Natural gas (Dths)	25,806	36,532	8,805	218	—	71,361
Coal (tons)	836	1,490	1,899	1,073	1,113	6,411
IPL
Electricity (MWhs)	1,046	1,678	—	—	—	2,724
FTRs (MWhs)	3,340	5,558	—	—	—	8,898
Natural gas (Dths)	17,823	25,776	3,862	218	—	47,679
Coal (tons)	266	75	830	274	387	1,832
WPL
Electricity (MWhs)	1,046	2,268	1,553	1,314	1,314	7,495
FTRs (MWhs)	2,333	4,002	—	—	—	6,335
Natural gas (Dths)	7,983	10,756	4,943	—	—	23,682
Coal (tons)	570	1,415	1,069	799	726	4,579

Fair Value Of Financial Instruments

The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other long-term liabilities and deferred credits” on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
Commodity contracts	September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013
Current derivative assets		$63.9		$25.6		$44.0		$20.2		$19.9		$5.4
Non-current derivative assets	19.2		1.1		0.7		0.9		18.5		0.2
Current derivative liabilities	9.0		6.7		5.2		3.0		3.8		3.7
Non-current derivative liabilities	5.1		14.1		3.0		2.2		2.1		11.9

Gains And Losses From Derivative Instruments

Changes in unrealized gains (losses) from commodity derivative instruments were recorded with offsets to regulatory assets or regulatory liabilities on the balance sheets as follows (in millions):

	Alliant Energy						IPL						WPL
	2014			2013			2014			2013			2014			2013
Three Months Ended September 30
Regulatory assets		$8.3			$2.2			$7.3			($0.4	)		$1.0			$2.6
Regulatory liabilities	(6.2		)	(1.0		)	(2.0		)	3.6			(4.2		)	(4.6		)
Nine Months Ended September 30
Regulatory assets	13.8			(14.2		)	8.7			(4.6		)	5.1			(9.6		)
Regulatory liabilities	63.2			16.6			13.9			9.9			49.3			6.7

Credit Risk-related Contingent Features

The aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position, as well as amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered, were as follows (in millions):

	September 30, 2014						December 31, 2013
	Alliant Energy		IPL		WPL		Alliant Energy		IPL		WPL
Aggregate fair value		$14.1		$8.2		$5.9		$20.8		$5.2		$15.6
Credit support to be posted if triggered	13.9		8.2		5.7		20.8		5.2		15.6

Balance Sheet Offsetting

The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, derivative assets and derivative liabilities related to commodity contracts would have been presented on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	Gross				Gross				Gross
	(as reported)		Net		(as reported)		Net		(as reported)		Net
September 30, 2014
Derivative assets		$83.1		$72.2		$44.7		$39.8		$38.4		$32.4
Derivative liabilities	14.1		7.9		8.2		3.6		5.9		4.3
December 31, 2013
Derivative assets	26.7		23.5		21.1		19.5		5.6		4.0
Derivative liabilities	20.8		17.6		5.2		3.6		15.6		14.0

IPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of September 30, 2014, gross notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	2014	2015	2016	2017	2018	Total
Alliant Energy
Electricity (MWhs)	2,092	3,946	1,553	1,314	1,314	10,219
FTRs (MWhs)	5,673	9,560	—	—	—	15,233
Natural gas (Dths)	25,806	36,532	8,805	218	—	71,361
Coal (tons)	836	1,490	1,899	1,073	1,113	6,411
IPL
Electricity (MWhs)	1,046	1,678	—	—	—	2,724
FTRs (MWhs)	3,340	5,558	—	—	—	8,898
Natural gas (Dths)	17,823	25,776	3,862	218	—	47,679
Coal (tons)	266	75	830	274	387	1,832
WPL
Electricity (MWhs)	1,046	2,268	1,553	1,314	1,314	7,495
FTRs (MWhs)	2,333	4,002	—	—	—	6,335
Natural gas (Dths)	7,983	10,756	4,943	—	—	23,682
Coal (tons)	570	1,415	1,069	799	726	4,579

Fair Value Of Financial Instruments

The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other long-term liabilities and deferred credits” on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
Commodity contracts	September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013
Current derivative assets		$63.9		$25.6		$44.0		$20.2		$19.9		$5.4
Non-current derivative assets	19.2		1.1		0.7		0.9		18.5		0.2
Current derivative liabilities	9.0		6.7		5.2		3.0		3.8		3.7
Non-current derivative liabilities	5.1		14.1		3.0		2.2		2.1		11.9

Gains And Losses From Derivative Instruments

Changes in unrealized gains (losses) from commodity derivative instruments were recorded with offsets to regulatory assets or regulatory liabilities on the balance sheets as follows (in millions):

	Alliant Energy						IPL						WPL
	2014			2013			2014			2013			2014			2013
Three Months Ended September 30
Regulatory assets		$8.3			$2.2			$7.3			($0.4	)		$1.0			$2.6
Regulatory liabilities	(6.2		)	(1.0		)	(2.0		)	3.6			(4.2		)	(4.6		)
Nine Months Ended September 30
Regulatory assets	13.8			(14.2		)	8.7			(4.6		)	5.1			(9.6		)
Regulatory liabilities	63.2			16.6			13.9			9.9			49.3			6.7

Credit Risk-related Contingent Features

The aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position, as well as amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered, were as follows (in millions):

	September 30, 2014						December 31, 2013
	Alliant Energy		IPL		WPL		Alliant Energy		IPL		WPL
Aggregate fair value		$14.1		$8.2		$5.9		$20.8		$5.2		$15.6
Credit support to be posted if triggered	13.9		8.2		5.7		20.8		5.2		15.6

Balance Sheet Offsetting

The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, derivative assets and derivative liabilities related to commodity contracts would have been presented on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	Gross				Gross				Gross
	(as reported)		Net		(as reported)		Net		(as reported)		Net
September 30, 2014
Derivative assets		$83.1		$72.2		$44.7		$39.8		$38.4		$32.4
Derivative liabilities	14.1		7.9		8.2		3.6		5.9		4.3
December 31, 2013
Derivative assets	26.7		23.5		21.1		19.5		5.6		4.0
Derivative liabilities	20.8		17.6		5.2		3.6		15.6		14.0

WPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of September 30, 2014, gross notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	2014	2015	2016	2017	2018	Total
Alliant Energy
Electricity (MWhs)	2,092	3,946	1,553	1,314	1,314	10,219
FTRs (MWhs)	5,673	9,560	—	—	—	15,233
Natural gas (Dths)	25,806	36,532	8,805	218	—	71,361
Coal (tons)	836	1,490	1,899	1,073	1,113	6,411
IPL
Electricity (MWhs)	1,046	1,678	—	—	—	2,724
FTRs (MWhs)	3,340	5,558	—	—	—	8,898
Natural gas (Dths)	17,823	25,776	3,862	218	—	47,679
Coal (tons)	266	75	830	274	387	1,832
WPL
Electricity (MWhs)	1,046	2,268	1,553	1,314	1,314	7,495
FTRs (MWhs)	2,333	4,002	—	—	—	6,335
Natural gas (Dths)	7,983	10,756	4,943	—	—	23,682
Coal (tons)	570	1,415	1,069	799	726	4,579

Fair Value Of Financial Instruments

The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other long-term liabilities and deferred credits” on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
Commodity contracts	September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013		September 30, 2014		December 31, 2013
Current derivative assets		$63.9		$25.6		$44.0		$20.2		$19.9		$5.4
Non-current derivative assets	19.2		1.1		0.7		0.9		18.5		0.2
Current derivative liabilities	9.0		6.7		5.2		3.0		3.8		3.7
Non-current derivative liabilities	5.1		14.1		3.0		2.2		2.1		11.9

Gains And Losses From Derivative Instruments

Changes in unrealized gains (losses) from commodity derivative instruments were recorded with offsets to regulatory assets or regulatory liabilities on the balance sheets as follows (in millions):

	Alliant Energy						IPL						WPL
	2014			2013			2014			2013			2014			2013
Three Months Ended September 30
Regulatory assets		$8.3			$2.2			$7.3			($0.4	)		$1.0			$2.6
Regulatory liabilities	(6.2		)	(1.0		)	(2.0		)	3.6			(4.2		)	(4.6		)
Nine Months Ended September 30
Regulatory assets	13.8			(14.2		)	8.7			(4.6		)	5.1			(9.6		)
Regulatory liabilities	63.2			16.6			13.9			9.9			49.3			6.7

Credit Risk-related Contingent Features

The aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position, as well as amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered, were as follows (in millions):

	September 30, 2014						December 31, 2013
	Alliant Energy		IPL		WPL		Alliant Energy		IPL		WPL
Aggregate fair value		$14.1		$8.2		$5.9		$20.8		$5.2		$15.6
Credit support to be posted if triggered	13.9		8.2		5.7		20.8		5.2		15.6

Balance Sheet Offsetting

The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, derivative assets and derivative liabilities related to commodity contracts would have been presented on the balance sheets as follows (in millions):

	Alliant Energy				IPL				WPL
	Gross				Gross				Gross
	(as reported)		Net		(as reported)		Net		(as reported)		Net
September 30, 2014
Derivative assets		$83.1		$72.2		$44.7		$39.8		$38.4		$32.4
Derivative liabilities	14.1		7.9		8.2		3.6		5.9		4.3
December 31, 2013
Derivative assets	26.7		23.5		21.1		19.5		5.6		4.0
Derivative liabilities	20.8		17.6		5.2		3.6		15.6		14.0