Note 3 - Securities - Securities With Unrealized Losses (Details) $ in Thousands	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Count, less than 12 months	5	180
Collateralized mortgage obligations - residential, fair value	$ 13,033	$ 148,388
Unrealized loss, less than 12 months	$ (81)	$ (4,581)
Count, 12 months or more	208	54
Fair value, 12 months or more	$ 141,950	$ 58,835
Unrealized loss, 12 months or more	$ (5,489)	$ (3,707)
Count, total	213	234
Fair value, total	$ 154,983	$ 207,223
Unrealized loss, total	$ (5,570)	$ (8,288)
US States and Political Subdivisions Debt Securities [Member]
Count, less than 12 months	0	1
Collateralized mortgage obligations - residential, fair value	$ 0	$ 225
Unrealized loss, less than 12 months	$ 0	$ (15)
Count, 12 months or more	1	0
Fair value, 12 months or more	$ 229	$ 0
Unrealized loss, 12 months or more	$ (11)	$ 0
Count, total	1	1
Fair value, total	$ 229	$ 225
Unrealized loss, total	$ (11)	$ (15)
US Treasury Securities [Member]
Count, less than 12 months	0	147
Collateralized mortgage obligations - residential, fair value	$ 0	$ 104,439
Unrealized loss, less than 12 months	$ 0	$ (4,104)
Count, 12 months or more	181	53
Fair value, 12 months or more	$ 123,095	$ 58,664
Unrealized loss, 12 months or more	$ (5,231)	$ (3,699)
Count, total	181	200
Fair value, total	$ 123,095	$ 163,103
Unrealized loss, total	$ (5,231)	$ (7,803)
US Government-sponsored Enterprises Debt Securities [Member]
Count, less than 12 months	3	9
Collateralized mortgage obligations - residential, fair value	$ 12,922	$ 39,699
Unrealized loss, less than 12 months	$ (78)	$ (301)
Count, 12 months or more	3	0
Fair value, 12 months or more	$ 14,941	$ 0
Unrealized loss, 12 months or more	$ (59)	$ 0
Count, total	6	9
Fair value, total	$ 27,863	$ 39,699
Unrealized loss, total	$ (137)	$ (301)
Residential Mortgage-Backed Securities [Member]
Count, less than 12 months	2	18
Collateralized mortgage obligations - residential, fair value	$ 111	$ 3,016
Unrealized loss, less than 12 months	$ (3)	$ (143)
Count, 12 months or more	16	0
Fair value, 12 months or more	$ 2,652	$ 0
Unrealized loss, 12 months or more	$ (162)	$ 0
Count, total	18	18
Fair value, total	$ 2,763	$ 3,016
Unrealized loss, total	$ (165)	$ (143)
Collateralized Mortgage-Backed Securities [Member]
Count, less than 12 months	0	5
Collateralized mortgage obligations - residential, fair value	$ 0	$ 1,009
Unrealized loss, less than 12 months	$ 0	$ (18)
Count, 12 months or more	7	1
Fair value, 12 months or more	$ 1,033	$ 171
Unrealized loss, 12 months or more	$ (26)	$ (8)
Count, total	7	6
Fair value, total	$ 1,033	$ 1,180
Unrealized loss, total	$ (26)	$ (26)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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