Business Segment Information - Financial Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	$ 1,060	$ 1,638
Operating Income (Loss)	(501)	(7,311)
Other Income (Expense):
Other	(8)	(8)
General and administrative	(93)	(82)
Transaction, reorganization, and separation	(15)	(54)
Financing costs, net	(90)	(69)
NET LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(707)	(7,524)
Total Assets	17,679	39,606	$ 18,781
Write-down of the carrying value of Oil and Gas properties	488	7,220
U.S. [Member]
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	409	660
Operating Income (Loss)	58	(5,320)
Other Income (Expense):
Total Assets	6,990	21,577
Write-down of the carrying value of Oil and Gas properties	0	5,235
Canada [Member]
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	83	133
Operating Income (Loss)	(41)	(1,430)
Other Income (Expense):
Total Assets	1,380	5,288
Write-down of the carrying value of Oil and Gas properties	0	1,353
Egypt [Member]
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	365	532
Operating Income (Loss)	(206)	102
Other Income (Expense):
Total Assets	5,592	7,247
Write-down of the carrying value of Oil and Gas properties	163	0
North Sea [Member]
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	203	313
Operating Income (Loss)	(312)	(663)
Other Income (Expense):
Total Assets	3,653	5,376
Write-down of the carrying value of Oil and Gas properties	325	632
Other International [Member]
Segment Reporting Information [Line Items]
Oil and Gas Production Revenues	0	0
Operating Income (Loss)	0	0
Other Income (Expense):
Total Assets	$ 64	$ 118