Consolidated Condensed Statements of Cash Flows - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net loss		$ (594)	$ (52)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation and amortization(1)	[1]	223	265
Debt extinguishment costs		0	24
Deferred income taxes		69	(61)
Gain on sale of assets, net		0	(27)
Mark-to-market activity, net	[2]	369	(55)
(Income) from unconsolidated subsidiaries		(6)	(4)
Return on investments from unconsolidated subsidiaries		3	13
Stock-based compensation expense		57	8
Other		6	0
Change in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable		164	82
Derivative instruments, net		(150)	(29)
Other assets		(184)	33
Accounts payable and accrued expenses		(46)	(105)
Other liabilities		(26)	20
Net cash (used in) provided by operating activities		(115)	112
Cash flows from investing activities:
Purchases of property, plant and equipment		(114)	(91)
Proceeds from sale of Osprey Energy Center		0	162
Payments to Acquire Businesses, Net of Cash Acquired		0	(111)
Other		(1)	16
Net cash used in investing activities		(115)	(24)
Cash flows from financing activities:
Borrowings under First Lien Term Loans		0	396
Repayment of CCFC Term Loan, CCFC Term Loans and First Lien Term Loans		(10)	(161)
Repurchase of First Lien Notes		0	(453)
Proceeds from Lines of Credit		325	25
Repayments of project financing, notes payable and other		(43)	(44)
Distribution to noncontrolling interest holder		(2)	(6)
Financing costs		(6)	(26)
Payments for Repurchase of Common Stock		(79)	0
Shares repurchased for tax withholding on stock-based awards		(7)	(6)
Other		(20)	1
Net cash provided by (used in) financing activities		158	(274)
Net decrease in cash, cash equivalents and restricted cash		(72)	(186)
Cash, cash equivalents and restricted cash, beginning of period		443	606
Cash, cash equivalents and restricted cash, end of period		371	420
Cash paid during the period for:
Interest, net of amounts capitalized		110	141
Income taxes		4	3
Supplemental disclosure of non-cash investing activities:
Increase Decrease In Capital Expenditures Incurred But Not Yet Paid		$ (6)	$ 0

[1] Includes amortization recorded in Commodity revenue and Commodity expense associated with intangible assets and amortization recorded in interest expense associated with debt issuance costs and discounts.

[2] In addition to changes in market value on derivatives not designated as hedges, changes in mark-to-market gain (loss) also includes hedge ineffectiveness and adjustments to reflect changes in credit default risk exposure.