Segment Reporting - Table (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Revenues	$ 17,506,000,000	$ 12,316,000,000	$ 11,635,000,000
Depreciation, depletion and amortization	2,903,000,000	2,811,000,000	1,923,000,000
Impairment of natural gas and oil properties	0	3,315,000,000	0
Impairments of fixed assets and other	546,000,000	340,000,000	46,000,000
Interest expense	(227,000,000)	(77,000,000)	(44,000,000)
Earnings (losses) on investments	(226,000,000)	(103,000,000)	156,000,000
Gains (losses) on sales of investments	(7,000,000)	1,092,000,000	0
Losses on purchases of debt and extinguishment of other financing	(193,000,000)	(200,000,000)	(176,000,000)
Income (Loss) Before Income Taxes	1,442,000,000	(974,000,000)	2,880,000,000
Total Assets	41,782,000,000	41,611,000,000
Exploration and Production
Segment Reporting Information [Line Items]
Revenues	7,052,000,000	6,278,000,000	6,024,000,000
Marketing, Gathering And Compression
Segment Reporting Information [Line Items]
Revenues	9,559,000,000	5,431,000,000	5,090,000,000
Oilfield Services
Segment Reporting Information [Line Items]
Revenues	879,000,000	602,000,000	521,000,000
Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues	16,000,000	5,000,000	0
Reportable Subsegments [Member]
Segment Reporting Information [Line Items]
Revenues	17,506,000,000	12,316,000,000	11,635,000,000
Unrealized Gain (Loss) on Derivatives	(228,000,000)	(561,000,000)	789,000,000
Depreciation, depletion and amortization	2,903,000,000	2,811,000,000	1,923,000,000
Gain (Loss) on Disposition of Assets for Financial Service Operations	(302,000,000)	(267,000,000)	(437,000,000)
Impairment of natural gas and oil properties		3,315,000,000
Impairments of fixed assets and other	546,000,000	340,000,000	46,000,000
Interest expense	(227,000,000)	(77,000,000)	(44,000,000)
Earnings (losses) on investments	(226,000,000)	(103,000,000)	156,000,000
Gains (losses) on sales of investments	(7,000,000)	1,092,000,000
Losses on purchases of debt and extinguishment of other financing	(193,000,000)	(200,000,000)	(176,000,000)
Income (Loss) Before Income Taxes	1,442,000,000	(974,000,000)	2,880,000,000
Total Assets	41,782,000,000	41,611,000,000	41,835,000,000
Payments to Acquire Productive Assets	7,190,000,000	14,108,000,000	14,561,000,000
Intersubsegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments [Member] | Reportable Subsegments [Member] | Exploration and Production
Segment Reporting Information [Line Items]
Revenues	7,052,000,000	6,278,000,000	6,024,000,000
Unrealized Gain (Loss) on Derivatives	(228,000,000)	(561,000,000)	789,000,000
Depreciation, depletion and amortization	2,674,000,000	2,624,000,000	1,759,000,000
Gain (Loss) on Disposition of Assets for Financial Service Operations	2,000,000	14,000,000	3,000,000
Impairment of natural gas and oil properties		3,315,000,000
Impairments of fixed assets and other	27,000,000	28,000,000	0
Interest expense	(918,000,000)	(47,000,000)	(42,000,000)
Earnings (losses) on investments	3,000,000	0	0
Gains (losses) on sales of investments	0	(2,000,000)
Losses on purchases of debt and extinguishment of other financing	(193,000,000)	(200,000,000)	(176,000,000)
Income (Loss) Before Income Taxes	2,997,000,000	(1,798,000,000)	2,561,000,000
Total Assets	35,341,000,000	37,004,000,000	35,403,000,000
Payments to Acquire Productive Assets	6,198,000,000	12,044,000,000	12,201,000,000
Operating Segments [Member] | Reportable Subsegments [Member] | Marketing, Gathering And Compression
Segment Reporting Information [Line Items]
Revenues	17,129,000,000	10,895,000,000	10,336,000,000
Unrealized Gain (Loss) on Derivatives	0	0	0
Depreciation, depletion and amortization	46,000,000	54,000,000	55,000,000
Gain (Loss) on Disposition of Assets for Financial Service Operations	(329,000,000)	(298,000,000)	(441,000,000)
Impairment of natural gas and oil properties		0
Impairments of fixed assets and other	50,000,000	6,000,000	43,000,000
Interest expense	(24,000,000)	(20,000,000)	(15,000,000)
Earnings (losses) on investments	0	49,000,000	95,000,000
Gains (losses) on sales of investments	0	1,094,000,000
Losses on purchases of debt and extinguishment of other financing	0	0	0
Income (Loss) Before Income Taxes	511,000,000	1,665,000,000	745,000,000
Total Assets	2,430,000,000	2,291,000,000	4,047,000,000
Payments to Acquire Productive Assets	299,000,000	852,000,000	1,219,000,000
Operating Segments [Member] | Reportable Subsegments [Member] | Oilfield Services
Segment Reporting Information [Line Items]
Revenues	2,188,000,000	1,917,000,000	1,258,000,000
Unrealized Gain (Loss) on Derivatives	0	0	0
Depreciation, depletion and amortization	289,000,000	232,000,000	172,000,000
Gain (Loss) on Disposition of Assets for Financial Service Operations	(1,000,000)	10,000,000	1,000,000
Impairment of natural gas and oil properties		0
Impairments of fixed assets and other	75,000,000	60,000,000	3,000,000
Interest expense	(82,000,000)	(76,000,000)	(48,000,000)
Earnings (losses) on investments	(1,000,000)	0	0
Gains (losses) on sales of investments	0	0
Losses on purchases of debt and extinguishment of other financing	0	0	0
Income (Loss) Before Income Taxes	(51,000,000)	112,000,000	72,000,000
Total Assets	2,018,000,000	2,115,000,000	1,571,000,000
Payments to Acquire Productive Assets	272,000,000	658,000,000	657,000,000
Operating Segments [Member] | Reportable Subsegments [Member] | Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues	29,000,000	21,000,000	0
Unrealized Gain (Loss) on Derivatives	0	0	0
Depreciation, depletion and amortization	49,000,000	46,000,000	37,000,000
Gain (Loss) on Disposition of Assets for Financial Service Operations	26,000,000	7,000,000	0
Impairment of natural gas and oil properties		0
Impairments of fixed assets and other	394,000,000	246,000,000	0
Interest expense	(74,000,000)	(364,000,000)	(195,000,000)
Earnings (losses) on investments	(229,000,000)	(152,000,000)	61,000,000
Gains (losses) on sales of investments	(7,000,000)	0
Losses on purchases of debt and extinguishment of other financing	0	0	0
Income (Loss) Before Income Taxes	(727,000,000)	(478,000,000)	(168,000,000)
Total Assets	5,750,000,000	2,529,000,000	2,718,000,000
Payments to Acquire Productive Assets	421,000,000	554,000,000	484,000,000
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0
Intersegment Eliminations [Member] | Exploration and Production
Segment Reporting Information [Line Items]
Revenues	0	0	0
Intersegment Eliminations [Member] | Marketing, Gathering And Compression
Segment Reporting Information [Line Items]
Revenues	(7,570,000,000)	(5,464,000,000)	(5,246,000,000)
Intersegment Eliminations [Member] | Oilfield Services
Segment Reporting Information [Line Items]
Revenues	(1,309,000,000)	(1,315,000,000)	(737,000,000)
Intersegment Eliminations [Member] | Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues	(13,000,000)	(16,000,000)	0
Intersegment Eliminations [Member] | Reportable Subsegments [Member]
Segment Reporting Information [Line Items]
Revenues	(8,892,000,000)	(6,795,000,000)	(5,983,000,000)
Unrealized Gain (Loss) on Derivatives	0	0	0
Depreciation, depletion and amortization	(155,000,000)	(145,000,000)	(100,000,000)
Gain (Loss) on Disposition of Assets for Financial Service Operations	0	0	0
Impairment of natural gas and oil properties		0
Impairments of fixed assets and other	0	0	0
Interest expense	871,000,000	430,000,000	256,000,000
Earnings (losses) on investments	1,000,000	0	0
Gains (losses) on sales of investments	0	0
Losses on purchases of debt and extinguishment of other financing	0	0	0
Income (Loss) Before Income Taxes	(1,288,000,000)	(475,000,000)	(330,000,000)
Total Assets	(3,757,000,000)	(2,328,000,000)	(1,904,000,000)
Payments to Acquire Productive Assets	0	0	0
Intersegment Eliminations [Member] | Intersubsegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	$ 8,892,000,000	$ 6,795,000,000	$ 5,983,000,000