Consolidated Condensed Statements of Cash Flows (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013
Cash flows from operating activities:
Net income (loss)	$ 128		$ (195)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization expense(1)	322	[1]	315	[1]
Debt extinguishment costs	1		28
Deferred income taxes	(12)		(15)
Mark-to-market activity, net	(70)	[2]	24	[2]
(Income) from unconsolidated investments in power plants	(13)		(16)
Return on unconsolidated investments in power plants	13		16
Stock-based compensation expense	22		20
Other	1		0
Change in operating assets and liabilities:
Accounts receivable	(212)		(285)
Derivative instruments, net	(109)		1
Other assets	(40)		(182)
Accounts payable and accrued expenses	378		67
Other liabilities	(60)		47
Net cash provided by (used in) operating activities	349		(175)
Cash flows from investing activities:
Purchases of property, plant and equipment	(258)		(335)
Purchase of Guadalupe Energy Center, net of cash	(656)		0
Decrease in restricted cash	14		55
Other	0		(1)
Net cash used in investing activities	(900)		(281)
Cash flows from financing activities:
Borrowings under CCFC Term Loans	420		1,197
Repayment of CCFC Term Loans, CCFC Notes and First Lien Term Loans	(23)		(1,012)
Borrowings from project financing, notes payable and other	2		116
Repayments of project financing, notes payable and other	(55)		(43)
Financing costs	(10)		(27)
Stock repurchases	(297)		(362)
Proceeds from exercises of stock options	15		17
Other	0		1
Net cash provided by (used in) financing activities	52		(113)
Net decrease in cash and cash equivalents	(499)		(569)
Cash and cash equivalents, beginning of period	941		1,284
Cash and cash equivalents, end of period	442		715
Cash paid during the period for:
Interest, net of amounts capitalized	288		334
Income taxes	16		21
Supplemental disclosure of non-cash investing activities:
Change in capital expenditures included in accounts payable	$ 13		$ 17

[1] Includes depreciation and amortization included in fuel and purchased energy expense and interest expense on our Consolidated Condensed Statements of Operations

[2] In addition to changes in market value on derivatives not designated as hedges, changes in mark-to-market gain (loss) also includes de-designation of interest rate swap cash flow hedges and related reclassification from AOCI into earnings, hedge ineffectiveness and adjustments to reflect changes in credit default risk exposure.