Other Current Liabilities - Details of Other Current Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued operating expenses	$ 120	$ 139
Accrued exploration and development	475	637
Accrued compensation and benefits	99	166
Accrued interest	146	144
Accrued income taxes	54	47
Current debt	1	1
Current asset retirement obligation	36	36
Other	95	53
Total Other current liabilities	$ 1,026	$ 1,223