Schedule of Trade Accounts Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 216,477	$ 156,384
Allowance for sales credit memos	(4,631)	(1,540)
Total accounts receivable net	211,846	154,844
Trade accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	190,820	128,757
Unbilled accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 25,657	$ 27,627