Note 15 - Financial Derivatives - Cash Flow Swap Hedges (Details) - Interest Rate Swap [Member] - Cash Flow Hedging [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Notional		$ 119,136		$ 119,136
Weighted average fixed rate-pay		2.61%		2.61%
Weighted average variable rate-receive		0.19%		0.44%
Unrealized loss, net of taxes	[1]	$ (5,627)		$ (6,890)
Periodic net settlement of swaps	[2]	$ 711	$ 255

[1] Included in other comprehensive income.

[2] the amount of periodic net settlement of interest rate swaps was included in interest expense.