Quarterly report [Sections 13 or 15(d)]

Note 4 - Securities - Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Securities (Details)

v3.25.3
Note 4 - Securities - Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Securities (Details) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Available for sale, amortized cost $ 1,186,017 $ 1,207,059
Available for sale, gross unrealized gain 5,866 668
Available for sale, gross unrealized loss (13,739) (46,327)
Available for sale, fair value 1,178,144 1,161,400
Held to maturity, amortized cost 671,595 714,853
Held to maturity, gross unrealized gain 462 14
Held to maturity, gross unrealized loss (49,232) (75,371)
Held to maturity debt securities, fair value 622,825 639,496
US Treasury Securities [Member]    
Available for sale, amortized cost 669,701 617,350
Available for sale, gross unrealized gain 2,865 580
Available for sale, gross unrealized loss 0 (444)
Available for sale, fair value 672,566 617,486
Held to maturity, amortized cost 249,566 249,403
Held to maturity, gross unrealized gain 0 0
Held to maturity, gross unrealized loss (11,435) (19,632)
Held to maturity debt securities, fair value 238,131 229,771
Collateralized Mortgage-Backed Securities [Member]    
Available for sale, amortized cost 143,062 243,435
Available for sale, gross unrealized gain 835 49
Available for sale, gross unrealized loss (990) (24,210)
Available for sale, fair value 142,907 219,274
Held to maturity, amortized cost 413,677 457,365
Held to maturity, gross unrealized gain 462 14
Held to maturity, gross unrealized loss (37,440) (55,150)
Held to maturity debt securities, fair value 376,699 402,229
US States and Political Subdivisions Debt Securities [Member]    
Available for sale, amortized cost 10,364 10,516
Available for sale, gross unrealized gain 1 1
Available for sale, gross unrealized loss (630) (1,000)
Available for sale, fair value 9,735 9,517
Held to maturity, amortized cost 8,352 8,085
Held to maturity, gross unrealized gain 0 0
Held to maturity, gross unrealized loss (357) (589)
Held to maturity debt securities, fair value 7,995 7,496
Corporate Debt Securities [Member]    
Available for sale, amortized cost 362,890 335,758
Available for sale, gross unrealized gain 2,165 38
Available for sale, gross unrealized loss (12,119) (20,673)
Available for sale, fair value $ 352,936 $ 315,123