Note 3 - Investment Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Due within one year, AFS, amortized cost	$ 9,518
Due within one year, AFS, fair value	9,481
Due within one year, HTM, carrying value	16,029
Due within one year, HTM, fair value	15,815
Due after one year but within five years, AFS, amortized cost	158,324
Due after one year but within five years, AFS, fair value	151,417
Due after one year but within five years, HTM, carrying value	204,196
Due after one year but within five years, HTM, fair value	199,369
Due after five years but within 10 years, AFS, amortized cost	58,836
Due after five years but within 10 years, AFS, fair value	53,826
Due after five years but within 10 years, HTM, carrying value	26,451
Due after five years but within 10 years, HTM, fair value	26,290
Due after 10 years, AFS, amortized cost	170,886
Due after 10 years, AFS, fair value	159,793
Due after 10 years, HTM, carrying value	745
Due after 10 years, HTM, fair value	745
Mortgage-backed securities – government agencies, AFS, amortized cost	857,086
Mortgage-backed securities – government agencies, AFS, fair value	765,522
Mortgage backed securities - government agencies, HTM, carrying value	238,028
Mortgage backed securities - government agencies, HTM, fair value	218,627
Total available for sale debt securities, amortized cost	1,254,650	$ 1,190,379
Total available for sale debt securities, fair value	1,140,039	1,180,298
Total held to maturity debt securities, carrying value	485,449
Total held to maturity debt securities, fair value	$ 460,846	$ 0