Supplemental Financial Information - Accrued Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Deferred revenue	$ 35,274	$ 51,763
Payroll and benefits	29,933	30,296
Shorebase and administrative costs	27,696	17,275
Rig operating costs	26,111	21,123
Current operating lease liability	16,267	5,072
Accrued capital project/upgrade costs	8,805	7,075
Personal injury and other claims	5,413	6,495
Interest payable	3,017
Other	1,224	1,689
Total	$ 153,740	$ 140,788