Schedule of Estimated Accrued Rebates Reserve for Cash Discounts and Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accrued Rebates
Supplemental Balance Sheet Information [Line Items]
Balance at Beginning of Period	$ 32,553	$ 14,859	$ 10,429
Provision for Current Period Sales	44,347	45,356	24,431
Provision/(Reversals) for Prior Period Sales	(5,205)	(1,245)	(1,159)
Actual Charges Related to Current Period Sales	(23,879)	(18,421)	(12,768)
Actual Charges Related to Prior Period Sales	(13,079)	(7,996)	(6,074)
Balance at End of Period	34,737	32,553	14,859
Reserve for Cash Discount
Supplemental Balance Sheet Information [Line Items]
Balance at Beginning of Period	831	688	388
Provision for Current Period Sales	8,889	7,402	6,435
Provision/(Reversals) for Prior Period Sales	(22)	0	0
Actual Charges Related to Current Period Sales	(8,160)	(6,722)	(5,747)
Actual Charges Related to Prior Period Sales	(650)	(537)	(388)
Balance at End of Period	888	831	688
Sales Return Reserve
Supplemental Balance Sheet Information [Line Items]
Balance at Beginning of Period	40	0	907
Provision for Current Period Sales	0	40	0
Provision/(Reversals) for Prior Period Sales	(40)	0	(907)
Actual Charges Related to Current Period Sales	0	0	0
Actual Charges Related to Prior Period Sales	0	0	0
Balance at End of Period	0	40	0
Allowance for Doubtful Accounts
Supplemental Balance Sheet Information [Line Items]
Balance at Beginning of Period	93	490	529
Provision for Current Period Sales	0	0	410
Provision/(Reversals) for Prior Period Sales	(20)	(397)	(319)
Actual Charges Related to Current Period Sales	0	0	0
Actual Charges Related to Prior Period Sales	0	0	(130)
Balance at End of Period	$ 73	$ 93	$ 490