Allocation of Depreciation and Amortization Expense between Cost of Services and Selling, General and Administrative Expenses (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Property, Plant and Equipment [Line Items]      
Total depreciation and amortization $ 8,462 $ 6,047 $ 6,823
Cost of services      
Property, Plant and Equipment [Line Items]      
Total depreciation and amortization 7,536 4,603 4,697
Selling, general and administrative      
Property, Plant and Equipment [Line Items]      
Total depreciation and amortization $ 926 $ 1,444 $ 2,126