Supplemental Financial Information - Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Rig operating expenses	$ 48,894	$ 33,732
Payroll and benefits	46,560	45,619
Deferred revenue	11,371	9,522
Accrued capital project/upgrade costs	3,698	60,308
Interest payable	28,234	18,365
Personal injury and other claims	5,699	6,424
Other	10,199	8,189
Total	$ 154,655	$ 182,159