Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 3,270	$ 1,750
Additions charged to Expense or Revenue	602	260
Deductions and write-offs	0	0
Balance at End of Period	3,872	2,010
Allowance for product returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,262	841
Additions charged to Expense or Revenue	1,300	709
Deductions and write-offs	(911)	(606)
Balance at End of Period	1,651	944
Allowance for obsolescence
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	397	527
Additions charged to Expense or Revenue	235	130
Deductions and write-offs	(28)	(105)
Balance at End of Period	$ 604	$ 552