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Derivative Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2017, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	Electricity					FTRs					Natural Gas					Coal					Diesel Fuel
	MWhs			Years		MWhs			Years		Dths			Years		Tons			Years		Gallons			Years
Alliant Energy	1,976			2017-2018		20,106			2017-2018		157,939			2017-2026		6,060			2017-2019		8,064			2017-2019
IPL	—			—		12,495			2017-2018		68,421			2017-2026		2,163			2017-2019		—			—
WPL	1,976			2017-2018		7,611			2017-2018		89,518			2017-2026		3,897			2017-2018		8,064			2017-2019

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 liabilities” on the balance sheets as follows (in millions):

	Alliant Energy								IPL								WPL
Commodity contracts	June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016
Current derivative assets		$35.9				$29.4				$28.7				$19.1				$7.2				$10.3
Non-current derivative assets	2.0				12.0				0.6				1.7				1.4				10.3
Current derivative liabilities	17.8				13.3				4.1				2.7				13.7				10.6
Non-current derivative liabilities	27.6				15.3				12.2				5.6				15.4				9.7

IPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2017, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	Electricity					FTRs					Natural Gas					Coal					Diesel Fuel
	MWhs			Years		MWhs			Years		Dths			Years		Tons			Years		Gallons			Years
Alliant Energy	1,976			2017-2018		20,106			2017-2018		157,939			2017-2026		6,060			2017-2019		8,064			2017-2019
IPL	—			—		12,495			2017-2018		68,421			2017-2026		2,163			2017-2019		—			—
WPL	1,976			2017-2018		7,611			2017-2018		89,518			2017-2026		3,897			2017-2018		8,064			2017-2019

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 liabilities” on the balance sheets as follows (in millions):

	Alliant Energy								IPL								WPL
Commodity contracts	June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016
Current derivative assets		$35.9				$29.4				$28.7				$19.1				$7.2				$10.3
Non-current derivative assets	2.0				12.0				0.6				1.7				1.4				10.3
Current derivative liabilities	17.8				13.3				4.1				2.7				13.7				10.6
Non-current derivative liabilities	27.6				15.3				12.2				5.6				15.4				9.7

WPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2017, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):

	Electricity					FTRs					Natural Gas					Coal					Diesel Fuel
	MWhs			Years		MWhs			Years		Dths			Years		Tons			Years		Gallons			Years
Alliant Energy	1,976			2017-2018		20,106			2017-2018		157,939			2017-2026		6,060			2017-2019		8,064			2017-2019
IPL	—			—		12,495			2017-2018		68,421			2017-2026		2,163			2017-2019		—			—
WPL	1,976			2017-2018		7,611			2017-2018		89,518			2017-2026		3,897			2017-2018		8,064			2017-2019

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 liabilities” on the balance sheets as follows (in millions):

	Alliant Energy								IPL								WPL
Commodity contracts	June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016				June 30, 2017				December 31, 2016
Current derivative assets		$35.9				$29.4				$28.7				$19.1				$7.2				$10.3
Non-current derivative assets	2.0				12.0				0.6				1.7				1.4				10.3
Current derivative liabilities	17.8				13.3				4.1				2.7				13.7				10.6
Non-current derivative liabilities	27.6				15.3				12.2				5.6				15.4				9.7

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Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

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Tabular disclosure of the notional amounts of outstanding derivative positions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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