INCOME TAXES - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Net operating loss carryforward	$ 10,144	$ 9,764
Inventory differences	570	1,222
Equity compensation	591	688
Investment in subsidiaries	3,514	581
Restructuring	1,389	2,328
Purchased goodwill	3,331	0
Accrued employee compensation and benefits	979	841
Other, net	144	423
Gross deferred tax assets	20,662	15,847
Less valuation allowances	(18,063)	(11,679)
Total deferred tax assets	2,599	4,168
Deferred tax liabilities:
Purchased intangible assets and goodwill	(2,644)	(4,013)
Depreciation and amortization	(267)	(1,130)
Other, net	(163)	(473)
Total deferred tax liabilities	(3,074)	(5,616)
Net deferred tax liabilities	$ (475)	$ (1,448)