Note 4 - Other Assets (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 14, 2020
Deposits Assets, Noncurrent	$ 554,000	$ 134,000
US Bureau of Land Management (“BLM”) [Member] \| Other Noncurrent Assets [Member]
Deposits Assets, Noncurrent	420,000		$ 420,000
Prepaid Rent [Member]
Amortization of Deferred Charges, Total	$ 115,000	$ 115,000

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_DepositsAssetsNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant