Securities - Amortized cost and fair value (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	$ 1,333,778	$ 1,361,797
Unrealized Gains	3,282	3,127
Unrealized Losses	(154,565)	(168,934)
Fair Value	1,182,495	1,195,990
U.S. Government agencies
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	88,079	90,649
Unrealized Gains	4	3
Unrealized Losses	(10,184)	(11,670)
Fair Value	77,899	78,982
Mortgage Backed Securities - residential
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	614,621	630,556
Unrealized Gains	132	15
Unrealized Losses	(78,911)	(89,251)
Fair Value	535,842	541,320
Mortgage Backed Securities - commercial
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	14,136	14,182
Unrealized Gains	1	2
Unrealized Losses	(415)	(523)
Fair Value	13,722	13,661
Collateralized mortgage obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	184,919	190,552
Unrealized Gains	28	29
Unrealized Losses	(25,651)	(27,555)
Fair Value	159,296	163,026
State and municipal obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	390,864	394,696
Unrealized Gains	186	171
Unrealized Losses	(34,596)	(34,539)
Fair Value	356,454	360,328
Municipal taxable
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	41,159	41,162
Unrealized Gains	29	11
Unrealized Losses	(4,808)	(5,396)
Fair Value	36,380	35,777
Collateralized debt obligations
Amortized cost and fair value of investments classified as available for sale
Unrealized Gains	2,902	2,896
Fair Value	$ 2,902	$ 2,896