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Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Securities, held-to-maturity, Amortized Cost	$ 51,186		$ 51,838
Securities held-to-maturity, Allowance for Credit Losses	(355)	$ (359)	(353)	$ (1,089)	$ (1,084)	$ (1,087)
Securities held-to-maturity, Net Carrying Amount	50,831		51,485
Securities held-to-maturity, Gross Unrecognized Losses	(5,745)		(6,767)
Securities held-to-maturity, Fair Value	45,086		44,718
Total Securities available for sale, before allowance for credit losses	1,396,817		1,506,798
Total Securities available for sale, Allowance for Credit Losses	(3,066)	$ (2,627)	(2,627)	$ 0
Total Securities available for sale, Gross Unrealized Gains	5,653		3,069
Total Securities available for sale, Gross Unrealized Losses	(7,617)		(9,335)
Total Securities available for sale, Fair Value	1,391,787		1,497,905
Total other securities
Total Securities available for sale, before allowance for credit losses	570,937		593,928
Total Securities available for sale, Allowance for Credit Losses	(3,066)		(2,627)
Total Securities available for sale, Gross Unrealized Gains	1,745		1,938
Total Securities available for sale, Gross Unrealized Losses	(6,585)		(6,970)
Total Securities available for sale, Fair Value	563,031		586,269
Municipals
Securities, held-to-maturity, Amortized Cost	43,360		44,002
Securities held-to-maturity, Allowance for Credit Losses	(355)		(353)
Securities held-to-maturity, Net Carrying Amount	43,005		43,649
Securities held-to-maturity, Gross Unrecognized Losses	(5,065)		(5,834)
Securities held-to-maturity, Fair Value	37,940		37,815
Total Securities available for sale, before allowance for credit losses	20,627		20,627
Total Securities available for sale, Allowance for Credit Losses	(3,066)		(2,627)
Total Securities available for sale, Gross Unrealized Losses	(683)
Total Securities available for sale, Fair Value	16,878		18,000
U.S. government agencies
Total Securities available for sale, before allowance for credit losses	7,510		8,804
Total Securities available for sale, Gross Unrealized Gains	40		77
Total Securities available for sale, Gross Unrealized Losses	(28)		(33)
Total Securities available for sale, Fair Value	7,522		8,848
Corporate
Total Securities available for sale, before allowance for credit losses	145,038		130,882
Total Securities available for sale, Gross Unrealized Gains	1,143		735
Total Securities available for sale, Gross Unrealized Losses	(4,554)		(6,368)
Total Securities available for sale, Fair Value	141,627		125,249
Mutual funds
Total Securities available for sale, before allowance for credit losses	12,291		11,890
Total Securities available for sale, Fair Value	12,291		11,890
Collateralized loan obligations
Total Securities available for sale, before allowance for credit losses	384,043		420,260
Total Securities available for sale, Gross Unrealized Gains	562		1,126
Total Securities available for sale, Gross Unrealized Losses	(1,320)		(569)
Total Securities available for sale, Fair Value	383,285		420,817
Other
Total Securities available for sale, before allowance for credit losses	1,428		1,465
Total Securities available for sale, Fair Value	1,428		1,465
Collateralized Mortgage Backed Securities
Total Securities available for sale, before allowance for credit losses	825,880		912,870
Total Securities available for sale, Gross Unrealized Gains	3,908		1,131
Total Securities available for sale, Gross Unrealized Losses	(1,032)		(2,365)
Total Securities available for sale, Fair Value	828,756		911,636
REMIC and CMO
Total Securities available for sale, before allowance for credit losses	632,223		707,540
Total Securities available for sale, Gross Unrealized Gains	1,748		1,107
Total Securities available for sale, Gross Unrealized Losses	(1,013)		(1,067)
Total Securities available for sale, Fair Value	632,958		707,580
GNMA
Total Securities available for sale, before allowance for credit losses	28,926		30,099
Total Securities available for sale, Gross Unrealized Gains	143
Total Securities available for sale, Gross Unrealized Losses	(6)		(154)
Total Securities available for sale, Fair Value	29,063		29,945
FNMA
Securities, held-to-maturity, Amortized Cost	7,826		7,836
Securities held-to-maturity, Net Carrying Amount	7,826		7,836
Securities held-to-maturity, Gross Unrecognized Losses	(680)		(933)
Securities held-to-maturity, Fair Value	7,146		6,903
Total Securities available for sale, before allowance for credit losses	94,083		99,183
Total Securities available for sale, Gross Unrealized Gains	1,097		11
Total Securities available for sale, Gross Unrealized Losses	(13)		(1,048)
Total Securities available for sale, Fair Value	95,167		98,146
FHLMC
Total Securities available for sale, before allowance for credit losses	70,648		76,048
Total Securities available for sale, Gross Unrealized Gains	920		13
Total Securities available for sale, Gross Unrealized Losses			(96)
Total Securities available for sale, Fair Value	$ 71,568		$ 75,965