SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments	$ 32,000,000	$ 160,000,000	$ 39,000,000	$ 23,000,000	$ 144,000,000	$ 951,000,000	$ 238,000,000	$ 42,000,000	$ 8,000,000	$ 1,103,000,000	$ 9,472,000,000
UK Petroleum Revenue Tax (PRT) rate										0.00%	35.00%
Total asset impairment charges										$ 1,100,000,000	$ 9,500,000,000
Impairment charge of Petroleum Revenue Tax benefits, before tax										486,000,000
Inventory write-downs										55,000,000	55,000,000
Goodwill impairment charges									0	0	163,000,000
Impairment of equity method investment											148,000,000
Restricted cash	0				0				0	0
Cash and cash equivalents	1,668,000,000				1,377,000,000				1,668,000,000	1,377,000,000	1,467,000,000	$ 679,000,000
Allowance for doubtful accounts	84,000,000				93,000,000				84,000,000	93,000,000	103,000,000	$ 98,000,000
Oil and gas property, fair value					306,000,000					306,000,000	3,900,000,000
Gathering, transmission and processing facilities	1,376,000,000				976,000,000				1,376,000,000	976,000,000
Accumulated depreciation	25,643,000,000				27,882,000,000				25,643,000,000	27,882,000,000
Impairment of GTP assets									0	135,000,000	1,700,000,000
Fair value of GTP assets					142,000,000					142,000,000	306,000,000
Gain (loss) on sale of oil and gas properties										21,000,000	135,000,000
Accounts payable									76,000,000	86,000,000
Net cost of third party gas									$ 254,000,000	159,000,000	105,000,000
Maximum percentage of production available to contract partners									40.00%
Other foreign currency gains (losses)									$ (11,000,000)	(25,000,000)	(11,000,000)
Egypt
Schedule Of Significant Accounting Policies [Line Items]
Goodwill impairment charges									0	0	0
Impairment of GTP assets											1,100,000,000
Canada
Schedule Of Significant Accounting Policies [Line Items]
Impairment of GTP assets											555,000,000
United States
Schedule Of Significant Accounting Policies [Line Items]
Impairment of GTP assets											103,000,000
North Sea
Schedule Of Significant Accounting Policies [Line Items]
Goodwill impairment charges									0	0	163,000,000
Gain (loss) on sale of oil and gas properties									6,000,000
Accounting Standards Update 2016-09, Excess Tax Benefit Component
Schedule Of Significant Accounting Policies [Line Items]
Deferred tax asset				$ 4,000,000
Retained Earnings (Accumulated Deficit) | Accounting Standards Update 2016-09
Schedule Of Significant Accounting Policies [Line Items]
Cumulative effect of new accounting principle adopted					$ (11,000,000)					$ (11,000,000)
Scottish Area Gas Evacuation System | North Sea
Schedule Of Significant Accounting Policies [Line Items]
Equity ownership percentage					30.28%					30.28%
Beryl Pipeline | North Sea
Schedule Of Significant Accounting Policies [Line Items]
Equity ownership percentage					60.56%					60.56%
Oil and Gas Properties, Proved
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment									0	$ 427,000,000	7,389,000,000
GTC facilities
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment										135,000,000	1,700,000,000
Gathering, transmission and processing facilities	1,400,000,000				$ 976,000,000				1,400,000,000	976,000,000
Accumulated depreciation	194,000,000				130,000,000				194,000,000	130,000,000
Gain (loss) on sale of oil and gas properties										0	$ 59,000,000
Other Property and Equipment
Schedule Of Significant Accounting Policies [Line Items]
Accumulated depreciation	$ 739,000,000				$ 780,000,000				$ 739,000,000	$ 780,000,000
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Voting interest required for consolidation of investments	50.00%								50.00%
Maximum | Other Property and Equipment
Schedule Of Significant Accounting Policies [Line Items]
Useful lives of gas gathering, transmission and processing facilities									20 years
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Voting interest required for consolidation of investments	50.00%								50.00%
Minimum | Other Property and Equipment
Schedule Of Significant Accounting Policies [Line Items]
Useful lives of gas gathering, transmission and processing facilities									3 years