Note 5 - Goodwill and Core Deposit Intangibles - Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Balance at beginning of period	$ 136,529	$ 12,513	$ 12,513	$ 12,513	$ 12,513
Goodwill acquired	0	0	124,016	0
Recast adjustments	(699)	0	(699)	0
Impairment	0	0	0	0	0
Balance at end of period	$ 135,830	$ 12,513	$ 135,830	$ 12,513	$ 12,513

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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