Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued compensation	$ 16,992		$ 18,925
Accrued income tax and sales tax	70		71
Customer deposits	0		3,970
Provision for forward loss reserves	0		1,226
Other	5,407		4,137
Total	$ 22,469	$ 22,238	$ 28,329