Select Condensed Consolidated Balance Sheet Details - Inventories, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 5,242	$ 4,969
Work-in-process	548	502
Finished goods	40,095	37,933
Inventory, gross, total	45,885	43,404
Less reserve for excess and obsolete finished goods	(16,897)	(16,112)
Inventories, net	$ 28,988	$ 27,292

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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