SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Allowance for doubtful accounts
Schedule of Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Year	$ 261	$ 213
Additions Charged to Costs and Expenses	562	369
Additions Charged to other Accounts	0	0
Deductions	(360)	(321)
Balance at End of Year	463	261
Allowance for obsolete inventories
Schedule of Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Year	1,265	2,142
Additions Charged to Costs and Expenses	343	480
Additions Charged to other Accounts	0	0
Deductions	(1,227)	(1,357)
Balance at End of Year	381	1,265
Valuation allowance for deferred tax assets
Schedule of Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Year	9,028	9,745
Additions Charged to Costs and Expenses	463	180
Additions Charged to other Accounts	0	0
Deductions	(1,033)	(897)
Balance at End of Year	8,458	9,028
Reserve for sales returns
Schedule of Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Year	147	207
Additions Charged to Costs and Expenses	1,334	1,446
Additions Charged to other Accounts	0	0
Deductions	(1,352)	(1,506)
Balance at End of Year	$ 129	$ 147