Note 4 - Premises and Equipment, Net (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Depreciation, Total	$ 5.8	$ 5.2	$ 3.9
Operating Lease, Weighted Average Remaining Lease Term (Year)	2 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent	4.71%
Operating Lease, Expense	$ 0.6	0.6	$ 0.5
Lessee, Operating Lease, Liability, to be Paid, Total	3.6	3.4
Lessee, Operating Lease, Liability, to be Paid, Year One	0.8	0.6
Lessee, Operating Lease, Liability, to be Paid, Year Two and Year Three	1.4	1.2
Lessee, Operating Lease, Liability, to be Paid, Year Four and Year Five	0.3	0.5
Lessee, Operating Lease, Liability, to be Paid, after Year Five	1.1	1.1
Premises and Equipment, Net [Member]
Operating Lease, Right-of-Use Asset	2.9	1.1
Other Liabilities [Member]
Operating Lease, Liability, Total	$ 2.8	$ 0.9
Minimum [Member]
Lessee, Operating Lease, Renewal Term (Year)	3 years
Maximum [Member]
Lessee, Operating Lease, Renewal Term (Year)	5 years