Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 4,086	$ 2,504	$ 3,270	$ 1,750
Additions charged to Expense or Revenue	800	800	1,635	1,560
Deductions and write-offs	(536)	(172)	(555)	(178)
Balance at End of Period	4,350	3,132	4,350	3,132
Allowance for product returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	2,191	1,030	1,262	841
Additions charged to Expense or Revenue	2,591	906	5,917	2,349
Deductions and write-offs	(2,520)	(407)	(4,917)	(1,661)
Balance at End of Period	2,262	1,529	2,262	1,529
Allowance for obsolescence
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,780	553	397	527
Additions charged to Expense or Revenue	339	227	1,910	447
Deductions and write-offs	(1,411)	(87)	(1,599)	(281)
Balance at End of Period	$ 708	$ 693	$ 708	$ 693