Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2015

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Commodity Price Risk (Non-trading) - Economic Activity - Pre-tax Gains (Losses) Associated with Economic Activity

The unrealized gains (losses) for economic activity for the years ended December 31 were as follows.

	2015			2014			2013
Operating Revenues
Wholesale energy (a)	$	115		$	72		$	(267	)
Retail energy	(9		)	29			12
Operating Expenses
Fuel	15			(27		)	(4		)
Energy purchases (a)	60			(74		)	132

(a) In the third quarter of 2015, Talen Energy refined an input used in its valuation technique for certain PJM basis curves as observable inputs became available. This change resulted in the recording of a $30 million net unrealized gain, primarily reflected in "Wholesale energy" revenue on the Statement of Income.

Commodity Volumes - Volumes of Derivative (Sales) Purchase Contracts

At December 31, 2015, the net volumes of derivative (sales)/purchase contracts used in support of the various strategies discussed above were as follows.

		Volumes (a)
Commodity	Unit of Measure	2016		2017		2018		Thereafter
Power	MWh	(36,420,569	)	(4,474,975	)	(568,082	)	(334,101	)
Capacity	MW-Month	(5,953	)	6		3		—
Gas	MMBtu	146,474,333		17,898,993		14,987,372		3,063,441
FTRs	MW-Month	8,724		200		—		—
Oil	Barrels	65,559		—		—		—
CRRs	MWh	2,491,444		538,584		—		—
Emission Allowances	Tons	75,617		—		—		—

(a) Volumes for option contracts factor in the probability of an option being exercised and may be less than the notional amount of the option.   

Fair Value and Balance Sheet Location of Derivative Instruments

The following table presents the fair value and location of commodity derivative instruments not designated as hedging instruments recorded on the Balance Sheets. 

	December 31, 2015				December 31, 2014
	Assets		Liabilities		Assets		Liabilities
Current:
Price Risk Management Assets/Liabilities:	$	562	$	431	$	1,079	$	1,024
Noncurrent:
Price Risk Management Assets/Liabilities:	131		108		239		193
Total derivatives	$	693	$	539	$	1,318	$	1,217

Pre-tax Gain (Loss) on Derivative Instruments Recognized in Income or on the Balance Sheet

The following tables present the pre-tax effect of derivative instruments recognized in income.

		Gain (Loss) Reclassified from AOCI into Income (Effective Portion)
Derivative Relationships	Location of Gain (Loss) Recognized in Income on Derivative	2015			2014		2013
Cash Flow Hedges:
Commodity contracts	Wholesale energy	$	(3	)	$	1	$	240
	Energy purchases	33			31		(58		)
	Depreciation	1			2		2
	Discontinued operations	—			8		23
	Total	$	31		$	42	$	207

Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative	2015			2014			2013
Commodity contracts	Wholesale energy	$	742		$	(505	)	$	(9	)
	Retail energy	22			30			25
	Fuel	(6		)	(30		)	2
	Energy purchases	(452		)	165			40
	Discontinued operations	—			6			14
	Total	$	306		$	(334	)	$	72

Derivative Positions Eligible for Offset with Related Cash Collateral

The table below summarizes the energy commodities derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged.             

	Assets								Liabilities
			Eligible for Offset								Eligible for Offset
	Gross		Derivative Instruments		Cash Collateral Received		Net		Gross		Derivative Instruments		Cash Collateral Pledged		Net
December 31, 2015	$	693	$	437	$	74	$	182	$	539	$	437	$	30	$	72
December 31, 2014	$	1,318	$	1,060	$	10	$	248	$	1,217	$	1,060	$	58	$	99

Derivative Positions Eligible for Offset with Related Cash Collateral

The table below summarizes the energy commodities derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged.             

	Assets								Liabilities
			Eligible for Offset								Eligible for Offset
	Gross		Derivative Instruments		Cash Collateral Received		Net		Gross		Derivative Instruments		Cash Collateral Pledged		Net
December 31, 2015	$	693	$	437	$	74	$	182	$	539	$	437	$	30	$	72
December 31, 2014	$	1,318	$	1,060	$	10	$	248	$	1,217	$	1,060	$	58	$	99