Note 12 - Derivative Financial Instruments - Effect of Derivative Instruments on Consolidated Statements of Income (Details) - Interest Rate Swap [Member] - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Net gain (loss)	[1]	$ (1,687)	$ 1,730
Not Designated as Hedging Instrument [Member]
Net gain (loss)	[1]	(1,050)	1,276
Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Net gain (loss)	[2]	$ (637)	$ 454

[1] Net gains and losses are recorded as part of "Net gain/loss from fair value adjustments" in the Consolidated Statements of Income.

[2] Net gains and losses recorded during the three months ended March 31, 2019, are recorded as part of "Interests and fees on loans" in the Consolidated Statements of Income. Net gains and losses recorded during the three months ended March 31, 2018, are recorded as part of "Net gain/loss from fair value adjustments" in the Consolidated Statements of Income.