Note 8 - Credit Losses - Impact of ASC 326 - Allowance for Credit Losses by Portfolio (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)
Beginning Balance	$ 1,661
Provision for expected credit losses	12
Beginning Balance	1,673
Trade Accounts Receivable [Member]
Beginning Balance	4,426
Provision for expected credit losses	120
Beginning Balance	4,546
Other Receivables [Member]
Beginning Balance	4,710
Provision for expected credit losses	2,024
Beginning Balance	$ 6,734