Note 8 - Accounts Payable and Accrued Liabilities - Components Accounts Payable and Accrued Liabilities in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued production fees	$ 1,946	$ 1,648
Accounts payable - trade	1,474	1,944
Accrued utilities and supplies	645	344
Other accrued liabilities	1,613	960
Total accounts payable and accrued liabilities	$ 5,678	$ 4,896