FEDERAL INCOME TAXES - Schedule of Components of Future Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
FEDERAL INCOME TAXES.
Net operating loss carryforwards	$ 13,795	$ 11,666
Mineral properties	11,682	10,301
Accrued vacation	22	22
Reclamation provision		149
Capital loss carryforwards	393	728
Restoration reserves	1,565	1,154
Capitalized transaction costs	1,162	1,168
Other	4,243	4,492
Deferred tax assets	32,862	29,680
Valuation allowance	$ (32,862)	(29,063)
Net deferred tax assets		617
Derivatives		(590)
Securities		(27)
Property, plant and equipment
Deferred tax liabilities		(617)
Net deferred tax asset (liability)

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=117330534&loc=d3e28680-109314

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319