Financial and Other Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2012

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair value of derivative instruments

The following tables present the fair value of derivative instruments as of December 31, 2012 and 2011:

	December 31, 2012					December 31, 2011
	Derivative Assets		Derivative Liabilities			Derivative Assets		Derivative Liabilities
	(In millions)
Derivatives designated as hedging instruments:
Interest rate contracts	$	—	$	(1	)	$	—	$	(1	)
Derivatives not designated as hedging instruments:
Foreign currency exchange contracts	$	—	$	—		$	3	$	(5	)
Commodity Contracts:
Natural Gas	645		(661		)	2,024		(2,080		)
Electricity	360		(351		)	747		(705		)
Other	11		(7		)	31		(20		)
Total derivatives not designated as hedging instruments:	$	1,016	$	(1,019	)	$	2,805	$	(2,810	)
Total derivatives:
Current	$	862	$	(879	)	$	2,272	$	(2,282	)
Noncurrent	154		(141		)	533		(529		)
Total derivatives	$	1,016	$	(1,020	)	$	2,805	$	(2,811	)

	December 31, 2012												December 31, 2011
	Derivative Assets						Derivative Liabilities						Derivative Assets						Derivative Liabilities
	Current			Noncurrent			Current			Noncurrent			Current			Noncurrent			Current			Noncurrent
	(In millions)
Reconciliation of derivative instruments to Consolidated Statements of Financial Position:
Total fair value of derivatives	$	862		$	154		$	(879	)	$	(141	)	$	2,272		$	533		$	(2,282	)	$	(529	)
Counterparty netting	(754		)	(115		)	754			115			(2,050		)	(440		)	2,050			440
Collateral adjustment	—			—			—			—			—			(19		)	74			—
Total derivatives as reported	$	108		$	39		$	(125	)	$	(26	)	$	222		$	74		$	(158	)	$	(89	)

Gain (Loss) Recognized in Income on Derivative

The effect of derivatives not designated as hedging instruments on the Consolidated Statements of Operations for years ended December 31, 2012 and 2011 is as follows:

	Location of Gain (Loss) Recognized in Income on Derivatives	Gain (Loss) Recognized in Income on Derivatives for Years Ended December 31
Derivatives not Designated as Hedging Instruments		2012			2011
		(In millions)
Foreign currency exchange contracts	Operating Revenue	$	—		$	(2	)
Commodity Contracts:
Natural Gas	Operating Revenue	(29		)	58
Natural Gas	Fuel, purchased power and gas	25			(21		)
Electricity	Operating Revenue	64			115
Other	Operating Revenue	5			9
Total		$	65		$	159

Volume of Commodity Contracts [Table Text Block]

Commodity	Number of Units
Natural Gas (MMBtu)	663,194,602
Electricity (MWh)	48,524,412
Foreign Currency Exchange ($ CAD)	10,838,396
FTR (MWh)	11,077,483