BUSINESS SEGMENT INFORMATION (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Segment	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of reporting segments | Segment			3
Segment Reporting Information [Line Items]
Revenue from contract with customers	$ 1,976,000,000	$ 1,389,000,000	$ 5,645,000,000	$ 4,247,000,000
Operating Income (Loss)	698,000,000	126,000,000	2,023,000,000	671,000,000
Other Income (Expense):
Gain on divestitures	1,000,000	296,000,000	10,000,000	616,000,000
Derivative instrument losses, net	(23,000,000)	(110,000,000)	(46,000,000)	(69,000,000)
Other	29,000,000	0	50,000,000	43,000,000
General and administrative	(99,000,000)	(98,000,000)	(330,000,000)	(307,000,000)
Transaction, reorganization, and separation	(8,000,000)	(20,000,000)	(20,000,000)	(14,000,000)
Financing costs, net	(192,000,000)	(101,000,000)	(385,000,000)	(300,000,000)
NET INCOME BEFORE INCOME TAXES	406,000,000	93,000,000	1,302,000,000	640,000,000
Total Assets	21,870,000,000	21,835,000,000	21,870,000,000	21,835,000,000	$ 21,922,000,000
Revenue from non-customer	198,000,000		534,000,000
Asset impairments	10,000,000	0	10,000,000	8,000,000
Operating Segments | United States
Segment Reporting Information [Line Items]
Revenue from contract with customers	879,000,000	550,000,000	2,495,000,000	1,593,000,000
Operating Income (Loss)	147,000,000	(114,000,000)	523,000,000	(71,000,000)
Other Income (Expense):
Total Assets	14,389,000,000	13,105,000,000	14,389,000,000	13,105,000,000
Asset impairments	39,000,000	160,000,000	76,000,000	212,000,000
Operating Segments | Canada
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	36,000,000	0	231,000,000
Operating Income (Loss)	0	(1,000,000)	0	(33,000,000)
Other Income (Expense):
Total Assets	0	0	0	0
Asset impairments				2,000,000
Operating Segments | Egypt
Segment Reporting Information [Line Items]
Revenue from contract with customers	759,000,000	543,000,000	2,161,000,000	1,655,000,000
Operating Income (Loss)	438,000,000	226,000,000	1,176,000,000	740,000,000
Other Income (Expense):
Total Assets	4,404,000,000	4,906,000,000	4,404,000,000	4,906,000,000
Operating Segments | North Sea
Segment Reporting Information [Line Items]
Revenue from contract with customers	338,000,000	260,000,000	989,000,000	768,000,000
Operating Income (Loss)	114,000,000	16,000,000	327,000,000	59,000,000
Other Income (Expense):
Total Assets	3,033,000,000	3,770,000,000	3,033,000,000	3,770,000,000
Asset impairments	10,000,000		10,000,000	8,000,000
Other International
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	0	0	0
Operating Income (Loss)	(1,000,000)	(1,000,000)	(3,000,000)	(24,000,000)
Other Income (Expense):
Total Assets	44,000,000	54,000,000	44,000,000	54,000,000
Oil
Segment Reporting Information [Line Items]
Revenue from contract with customers	1,555,000,000	1,070,000,000	4,524,000,000	3,292,000,000
Other Income (Expense):
Revenue from non-customer	181,000,000		485,000,000
Oil | Operating Segments | United States
Segment Reporting Information [Line Items]
Revenue from contract with customers	583,000,000	381,000,000	1,743,000,000	1,133,000,000
Oil | Operating Segments | Canada
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	14,000,000	0	110,000,000
Oil | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Revenue from contract with customers	669,000,000	442,000,000	1,887,000,000	1,351,000,000
Oil | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Revenue from contract with customers	303,000,000	233,000,000	894,000,000	698,000,000
Oil | Other International
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	0	0	0
Natural Gas
Segment Reporting Information [Line Items]
Revenue from contract with customers	241,000,000	238,000,000	675,000,000	726,000,000
Other Income (Expense):
Revenue from non-customer	16,000,000		47,000,000
Natural Gas | Operating Segments | United States
Segment Reporting Information [Line Items]
Revenue from contract with customers	125,000,000	97,000,000	331,000,000	266,000,000
Natural Gas | Operating Segments | Canada
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	19,000,000	0	104,000,000
Natural Gas | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Revenue from contract with customers	86,000,000	98,000,000	263,000,000	295,000,000
Natural Gas | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Revenue from contract with customers	30,000,000	24,000,000	81,000,000	61,000,000
Natural Gas | Other International
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	0	0	0
Natural gas liquids
Segment Reporting Information [Line Items]
Revenue from contract with customers	180,000,000	81,000,000	446,000,000	229,000,000
Other Income (Expense):
Revenue from non-customer	1,000,000		2,000,000
Natural gas liquids | Operating Segments | United States
Segment Reporting Information [Line Items]
Revenue from contract with customers	171,000,000	72,000,000	421,000,000	194,000,000
Natural gas liquids | Operating Segments | Canada
Segment Reporting Information [Line Items]
Revenue from contract with customers	0	3,000,000	0	17,000,000
Natural gas liquids | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Revenue from contract with customers	4,000,000	3,000,000	11,000,000	9,000,000
Natural gas liquids | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Revenue from contract with customers	5,000,000	3,000,000	14,000,000	9,000,000
Natural gas liquids | Other International
Segment Reporting Information [Line Items]
Revenue from contract with customers	$ 0	$ 0	$ 0	$ 0