CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
NET INCOME (LOSS)	$ (594)	$ 1,757	$ 1,774
ADJUSTMENTS TO RECONCILE NET INCOME (LOSS) TO CASH PROVIDED BY OPERATING ACTIVITIES:
Depreciation, depletion and amortization	2,811	1,923	1,614
Deferred income taxes	(427)	1,110	1,110
Non-Cash Unrealized (gains) losses on derivatives	(567)	796	592
Stock-based compensation	120	153	147
Gains on sales of fixed assets	(267)	(437)	(137)
Impairments of fixed assets and other	316	46	21
Impairment of natural gas and oil properties	3,315	0	0
(Gains) losses on investments	164	(41)	(107)
Gains on sales of investments	(1,092)	0	0
Impairments of investments	0	0	16
Losses on purchases or exchanges of debt	200	5	29
Other	74	(3)	110
Increase in accounts receivable and other assets	(68)	(530)	(769)
Increase (decrease) in accounts payable, accrued liabilities and other	(1,148)	1,124	717
Cash provided by operating activities	2,837	5,903	5,117
CASH FLOWS FROM INVESTING ACTIVITIES:
Drilling and completion costs	(8,930)	(7,467)	(5,242)
Acquisitions of proved and unproved properties	(3,161)	(4,974)	(6,945)
Proceeds from divestitures of proved and unproved properties	5,884	7,651	4,292
Additions to other property and equipment	(2,651)	(2,009)	(1,326)
Proceeds from sales of other assets	2,492	1,312	883
Proceeds from (additions to) investments	(395)	101	(134)
Proceeds from sale of midstream investment	2,000	0	0
Acquisition of drilling company	0	(339)	0
Increase in restricted cash	(222)	(44)	0
Other	(1)	(43)	(31)
Cash used in investing activities	(4,984)	(5,812)	(8,503)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from credit facilities borrowings	20,318	15,509	15,117
Payments on credit facilities borrowings	(21,650)	(17,466)	(13,303)
Proceeds from issuance of term loans, net of discount and offering costs	5,722	0	0
Proceeds from issuance of senior notes, net of discount and offering costs	1,263	1,614	1,967
Proceeds from issuance of preferred stock, net of offering costs	0	0	2,562
Cash paid to purchase debt	(4,000)	(2,015)	(3,434)
Cash paid for common stock dividends	(227)	(207)	(189)
Cash paid for preferred stock dividends	(171)	(172)	(92)
Cash (paid) received on financing derivatives	(37)	1,043	621
Proceeds from sales of noncontrolling interests	1,077	1,348	0
Proceeds from other financings	257	300	0
Distributions to noncontrolling interest owners	(218)	(9)	0
Net increase (decrease) in outstanding payments in excess of cash balance	(172)	353	20
Other	(79)	(140)	(88)
Cash provided by financing activities	2,083	158	3,181
Net increase (decrease) in cash and cash equivalents	(64)	249	(205)
Cash and cash equivalents, beginning of period	351	102	307
Cash and cash equivalents, end of period	287	351	102
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION OF NET CASH PAYMENTS (REFUNDS) FOR:
Interest, net of capitalized interest	0	0	11
Income taxes, net of refunds received	$ 44	$ (25)	$ (291)