Note 11 - Commitments and Contingencies (Details Textual)	Dec. 14, 2020 USD ($)	Dec. 04, 2020 USD ($)	Dec. 31, 2020 USD ($)	Jan. 24, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) item
Deposits Assets, Noncurrent			$ 554,000		$ 134,000
The 1904 Pipeline [Member]
Miles of Pipeline			96
US Bureau of Land Management (“BLM”) [Member]
Right of Way Agreement, Period (Year)	30 years
Right of Way Agreement, Annual Rent Expense	$ 321,000
US Bureau of Land Management (“BLM”) [Member] | Other Noncurrent Assets [Member]
Deposits Assets, Noncurrent	$ 420,000		$ 420,000
124-mile Extension Possible for Northern Pipeline, Available for Purchase [Member] | El Paso Natural Gas Company (“EPNG”) [Member]
Miles of Pipeline | item						124
Other Commitment, Total				$ 21,000,000		$ 20,000,000
Payments to Acquire Productive Assets, Total		$ 1,000,000
124-mile Extension Possible for Northern Pipeline, Available for Purchase [Member] | El Paso Natural Gas Company (“EPNG”) [Member] | Other Noncurrent Assets [Member]
Deposit Assets, Total						$ 2,000,000
Water Project [Member]
Deferred Revenue, Total			$ 750,000		$ 750,000