Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income (loss)	$ 56	$ (40)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	45	130
Net gain on sale or disposal of assets	(75)	(562)
Stock-based compensation	11	164
Changes in operating assets and liabilities:
Accounts receivable	120	113
Inventories	30	169
Other inventory supplies	43	68
Prepaid expenses and other assets	(107)	(106)
Accounts payable	(53)	(360)
Accrued payroll	83	(32)
Accrued real estate taxes	12	(13)
Corporate income and franchise taxes	(3)	55
Advanced payments	(23)	(47)
Accrued and other current liabilities	(58)	(61)
Net cash provided by (used in) operating activities	81	(522)
Cash flows from investing activities
Proceeds from sale or disposal of assets	75	1,188
Purchases of investments	(1,992)	(2,775)
Proceeds from sale of investments	119	544
Net cash used in investing activities	(1,798)	(1,043)
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards		(1)
Purchases of treasury stock	(32)
Net cash used in financing activities	(32)	(1)
Net effect of currency translation		(1)
Net decrease in cash, cash equivalents and restricted cash	(1,749)	(1,567)
Cash, cash equivalents and restricted cash, beginning of period	11,410	11,725
Cash, cash equivalents and restricted cash, end of period	$ 9,661	$ 10,158

Increase (decrease) during the period in corporate income and franchise taxes.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The increase (decrease) during the period in accrued salaries.

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The increase (decrease) during the period in the amount of cash payments due to taxing authorities for non-income-related taxes.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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