Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net income (loss)	$ (2,209)	$ 56
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	42	45
(Gain)/loss on disposal of assets		(75)
Unrealized (gain)/loss on investments	156
Realized (gain)/loss on investments	1,786
Stock-based compensation	11	11
Changes in operating assets and liabilities:
Accounts receivable	314	120
Inventories	316	30
Other inventory supplies	(1)	43
Prepaid expenses and other assets	29	(107)
Accounts payable	(291)	(53)
Accrued payroll	28	83
Accrued real estate taxes	19	12
Corporate income and franchise taxes	16	(3)
Advanced payments	(16)	(23)
Accrued and other current liabilities	(62)	(58)
Net cash provided by operating activities	138	81
Cash flows from investing activities
Proceeds from sale or disposal of assets		75
Purchases of investments	(1,720)	(1,992)
Proceeds from sale of investments	5,180	119
Net cash provided by (used in) investing activities	3,460	(1,798)
Cash flows from financing activities
Purchases of treasury stock	(1,205)	(32)
Net cash used in financing activities	(1,205)	(32)
Net effect of currency translation
Net increase (decrease) in cash, cash equivalents and restricted cash	2,393	(1,749)
Cash, cash equivalents and restricted cash, beginning of period	8,880	11,410
Cash, cash equivalents and restricted cash, end of period	$ 11,273	$ 9,661