Accrued and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Accrued payroll and employee benefits	$ 3,456	$ 6,975
Accrued insurance	3,109	2,664
Accrued legal	413	733
Accrued taxes	1,453	2,229
Accrued interest	319	520
Accrued operating costs	3,758	3,424
Accrued other	280	125
Current operating lease liabilities	1,945	0
Total accrued and other current liabilities	$ 14,733	$ 16,670