Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015		Jun. 30, 2014
Operating Revenues
Total operating revenues	$ 3,397	[1]	$ 3,621	[2]	$ 7,223	[1]	$ 7,107	[1]
Operating Costs and Expenses
Cost of operations	2,434		2,828		5,496		5,565
Depreciation and amortization	396		386		791		721
Selling, general and administrative	291		257		554		479
Acquisition-related transaction and integration costs	3		40		13		52
Development activity expenses	41		21		75		40
Total operating costs and expenses	3,165		3,532		6,929		6,857
Gain on postretirement benefits curtailment and sale of assets	0		0		14		19
Operating Income	232		89		308		269
Other Income/(Expense)
Equity in earnings of unconsolidated affiliates	8		14		5		21
Other income, net	4		5		23		16
Loss on debt extinguishment	(7)		(40)		(7)		(81)
Interest expense	(263)		(274)		(564)		(529)
Total other expense	(258)		(295)		(543)		(573)
Loss Before Income Taxes	(26)		(206)		(235)		(304)
Income tax benefit	(17)		(126)		(90)		(157)
Net Loss	(9)		(80)		(145)		(147)
Less: Net income/(loss) attributable to noncontrolling interest and redeemable noncontrolling interests	5		17		(11)		6
Net Loss Attributable to NRG Energy, Inc.	(14)		(97)		(134)		(153)
Dividends for preferred shares	5		3		10		5
Loss Available for Common Stockholders	$ (19)		$ (100)		$ (144)		$ (158)
Loss per Share Attributable to NRG Energy, Inc. Common Stockholders
Weighted average number of common shares outstanding - basic and diluted	333		337		335		331
Loss per Weighted Average Common Share — Basic and Diluted	$ (0.06)		$ (0.30)		$ (0.43)		$ (0.48)
Dividends Per Common Share	$ 0.14		$ 0.14		$ 0.29		$ 0.26

[1] (a) Operating revenues include inter-segment sales and net derivative gains and losses of:$295 $4 $— $23 $9 $48 $— $379

[2] (c) Operating revenues include inter-segment sales and net derivative gains and losses of:$712 $2 $— $15 $— $(43) $— $686