Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities
Net loss	$ (10,682)	$ (15,542)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	868	3,291
Net loss on disposal of assets	1,181	126
Asset impairment charge	675	265
Stock-based compensation	623	731
Deferred taxes		(337)
Changes in operating assets and liabilities:
Accounts receivable	2,004	(999)
Inventories	1,386	505
Inventory reserves	1,900	188
Other inventory supplies	256	232
Prepaid expenses and other assets	692	1,164
Accounts payable	(437)	330
Accrued payroll	109	49
Corporate income and franchise taxes	(101)	(97)
Advanced payments	(12)	20
Accrued and other current liabilities	(47)	(919)
Net cash used in operating activities	(1,585)	(10,993)
Cash flows from investing activities
Purchases of property and equipment		(660)
Proceeds from disposal of assets	1,849	190
Purchases of investments	(9)	(18)
Proceeds from sale of investments	21	7,912
Net cash provided by investing activities	1,861	7,424
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards	(173)	(1)
Restricted cash	(7)	(12)
Net cash used in financing activities	(180)	(13)
Net effect of currency translation	4	(567)
Net decrease in cash and cash equivalents	100	(4,149)
Cash and cash equivalents, beginning of period	17,672	21,216
Cash and cash equivalents, end of period	$ 17,772	$ 17,067