Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Income (loss) from continuing operations	$ 480	$ (712)
Adjustments to reconcile net income (loss) from continuing operations to net cash provided by (used in) continuing operations
Depreciation and amortization	30	38
Gain on sale or disposal of assets	(432)
Other gain	(189)
Stock-based compensation	18	341
Unrealized gain on equity investments, net	(7)
Changes in operating assets and liabilities:
Accounts receivable	306	50
Inventories	58	36
Other inventory supplies	(2)	1
Prepaid expenses and other assets	9	34
Accounts payable	(134)	(202)
Accrued payroll	69	(58)
Accrued real estate taxes	20	19
Corporate income and franchise taxes	(19)	22
Advanced payments	(1)	(8)
Accrued and other current liabilities	(76)	186
Net cash provided by (used in) continuing operations	130	(253)
Cash flows used in discontinued operations		(144)
Cash flows from investing activities
Purchase of property and equipment
Proceeds from sale or disposal of assets	432
Purchases of investments	(1,061)	(1)
Proceeds from sale of investments	3	1
Net cash used in investing activities	(626)
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards		(162)
Net cash used in financing activities		(162)
Net decrease in cash & cash equivalents	(496)	(559)
Cash, cash equivalents and restricted cash, beginning of period	11,260	11,130
Cash, cash equivalents and restricted cash, end of period	$ 10,764	$ 10,571

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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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