Note 7 - Credit Losses - Impact of ASC 326 - Allowance for Credit Losses by Portfolio (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Trade Accounts Receivable [Member]
Beginning Balance	$ 4,426
Provision for expected credit losses	171
Beginning Balance	4,597
Other Non-trade Contractual Arrangements [Member]
Beginning Balance	3,524
Provision for expected credit losses	3,424
Beginning Balance	$ 6,948