Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities
Net income (loss)	$ 820	$ (11,791)
Adjustments to reconcile net income (loss) to net cash used in operating activities
Depreciation and amortization	309	1,023
Net (gain) loss from sale or disposal of assets	(2,738)	1,135
Long-lived asset impairment charge		675
Stock-based compensation	359	786
Changes in operating assets and liabilities:
Accounts receivable	(68)	1,907
Inventories	468	3,907
Other inventory supplies	74	314
Prepaid expenses and other assets	130	789
Accounts payable	(321)	(241)
Accrued payroll	(21)	16
Corporate income and franchise taxes	(15)	(63)
Accrued real estate taxes	(206)	(27)
Advanced payments	(18)	50
Accrued and other current liabilities	(145)	(113)
Net cash used in operating activities	(1,372)	(1,633)
Cash flows from investing activities
Purchases of assets	(2,280)
Proceeds from sale or disposal of assets	10,387	2,144
Purchases of investments	(8,314)	(24)
Proceeds from sale of investments	184	37
Net cash (used in) provided by investing activities	(23)	2,157
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards	(9)	(173)
Net cash used in financing activities	(9)	(173)
Net effect of currency translation		9
Net increase (decrease) in cash and cash equivalents	(1,404)	360
Cash and cash equivalents, beginning of period	11,725	17,835
Cash and cash equivalents, end of period	$ 10,321	$ 18,195