Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Cash flows from continuing operating activities
Income (loss) from continuing operations	$ 1,016	$ (716)
Adjustments to reconcile net income (loss) from continuing operations to net cash used in continuing operations
Depreciation and amortization	60	74
Gain on sale or disposal of assets	(1,071)	(370)
Other gain	(189)
Stock-based compensation	37	371
Unrealized gain on equity investments, net	(11)
Changes in operating assets and liabilities:
Accounts receivable	(314)	(1)
Inventories	(58)	106
Other inventory supplies	(7)	2
Prepaid expenses and other assets	63	143
Grants receivable	(250)
Accounts payable	(47)	(108)
Accrued payroll	92	63
Accrued real estate taxes	(2)	3
Corporate income and franchise taxes	(27)	11
Advanced payments	(1)	(18)
Accrued and other current liabilities	108	13
Net cash used in continuing operations	(601)	(427)
Cash flows used in discontinued operations		(190)
Cash flows from investing activities
Proceeds from sale or disposal of assets	1,086	370
Purchases of investments	(1,091)	(3)
Proceeds from sale of investments	19	1
Net cash provided by investing activities	14	368
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards		(181)
Net cash used in financing activities		(181)
Net decrease in cash and cash equivalents	(587)	(430)
Cash and cash equivalents, beginning of period	11,260	11,130
Cash and cash equivalents, end of period	$ 10,673	$ 10,700

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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 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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