Cash flow information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss		$ (5,386,000)	$ (1,945,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		1,098,000	1,171,000
Accretion of asset retirement obligation		225,000	163,000
Loss (gain) on trading securities		217,000	(92,000)
Asset write off		19,000	13,000
Gain on reduction of asset retirement obligation		(63,000)
Gain on sale of assets		(3,144,000)	(5,144,000)
Stock compensation		782,000	226,000
Changes in operating assets and liabilities from continuing operations:
Decrease (increase) in lease receivable		33,000	(167,000)
Increase (decrease) in prepaid expenses and other assets		(37,000)	549,000
Increase (decrease) in inventories		(2,000)	13,000
Increase in derivative at fair value	$ (59,000)	(254,000)
Increase in other long term assets		(562,000)	(432,000)
(Decrease) increase in reclamation liability		(5,000)	24,000
Increase in accounts payable and accrued liabilities		514,000	236,000
Decrease in deferred revenue		(128,000)	(292,000)
Increase in other current liabilities		1,811,000
Increase (decrease) in other long term liabilities		484,000	(34,000)
Net cash used in operating activities		(4,395,000)	$ (5,711,000)
Other		$ 3,000