Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Loss from continuing operations	$ (535)	$ (407)
Adjustments to reconcile net loss from continuing operations to net cash provided by (used in) continuing operations
Depreciation and amortization	108	114
Gain on sale or disposal of assets	(613)	(1,823)
Stock-based compensation	371	46
Realized loss on equity investments, net		1,824
Changes in operating assets and liabilities:
Accounts receivable	(536)	23
Inventories	312	663
Other inventory supplies	5	1
Prepaid expenses and other assets	150	346
Accounts payable	78	(414)
Accrued payroll	132	(19)
Accrued real estate taxes	(13)	(60)
Corporate income and franchise taxes	15	7
Advanced payments	(18)	(16)
Accrued and other current liabilities	39	(167)
Net cash provided by (used in) continuing operations	(505)	118
Cash flows from discontinued operations	(178)	72
Cash flows from investing activities
Purchase of property and equipment		(2)
Proceeds from sale or disposal of assets	613	4,769
Purchases of investments	(3)	(2,779)
Proceeds from sale of investments	2	1,666
Net cash provided by investing activities	612	3,654
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards	(182)
Purchases of treasury stock		(2,399)
Net cash used in financing activities	(182)	(2,399)
Net increase (decrease) in cash, cash equivalents and restricted cash	(253)	1,446
Cash, cash equivalents and restricted cash, beginning of period	11,130	8,880
Cash, cash equivalents and restricted cash, end of period	$ 10,877	$ 10,326

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

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The increase (decrease) during the reporting period in the amount of prepayment by customers for goods or services to be provided at a later date.

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Proceeds from sale of investments.

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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 increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. 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 cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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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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Amount after tax of income (loss) from continuing operations attributable to the noncontrolling interest.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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Amount of increase (decrease) in accrued expenses, and obligations classified as other.

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

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The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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The increase (decrease) during the period in the carrying amount of capitalized costs of materials, supplies, or both, which are not included in inventory.

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Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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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, excluding 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 cash outflow to reacquire common stock during the period.

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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Aggregate cash proceeds received from a combination of transactions that are classified as investing activities in which assets, which may include one or more investments, are sold to third-party buyers. This element can be used by entities to aggregate proceeds from all asset sales that are classified as investing activities.

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Amount of noncash expense for share-based payment arrangement.

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