Short-term and long-term debt (Detail) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Short-term debt:
- Revolving credit line and other debt		$ 65,152	$ 0
- Long-term debt: current		1,050	199
Subtotal		66,202	199
Long-term debt:
- Term Loan Facility		103,950	0
- Vehicle and equipment loans		39	36
- Capital lease obligations		20	116
- Less: deferred financing costs on term loan		(2,851)	0
Subtotal		101,158	152
Total short-term & long-term debt	[1]	$ 167,360	$ 351

[1] Long-term debt is net of deferred financing costs.