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Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Securities
Securities, held-to-maturity, Amortized Cost	$ 50,191	$ 50,528
Securities held-to-maturity, Allowance for Credit Losses	(338)	(348)	$ (359)	$ (353)
Securities held-to-maturity, Net Carrying Amount	49,853	50,180
Securities held-to-maturity, Gross Unrecognized Losses	(4,641)	(3,948)
Securities held-to-maturity, fair value	45,212	46,232
Total Securities available for sale, Amortized Cost	1,633,466	1,387,619
Total Securities available for sale, Allowance for Credit Losses	(2,774)	(2,921)	$ (2,627)	$ (2,627)	$ 0
Total Securities available for sale, Gross Unrealized Gains	7,117	8,939
Total Securities available for sale, Gross Unrealized Losses	(9,222)	(3,713)
Total Securities available for sale, Fair Value	1,628,587	1,389,924
Total other securities
Securities
Total Securities available for sale, Amortized Cost	545,178	571,530
Total Securities available for sale, Allowance for Credit Losses	(2,774)	(2,921)
Total Securities available for sale, Gross Unrealized Gains	2,691	2,873
Total Securities available for sale, Gross Unrealized Losses	(3,756)	(3,496)
Total Securities available for sale, Fair Value	541,339	567,986
Municipals
Securities
Securities, held-to-maturity, Amortized Cost	42,379	42,711
Securities held-to-maturity, Allowance for Credit Losses	(338)	(348)
Securities held-to-maturity, Net Carrying Amount	42,041	42,363
Securities held-to-maturity, Gross Unrecognized Losses	(4,032)	(3,342)
Securities held-to-maturity, fair value	38,009	39,021
Total Securities available for sale, Amortized Cost	20,627	20,627
Total Securities available for sale, Allowance for Credit Losses	(2,774)	(2,921)
Total Securities available for sale, Gross Unrealized Losses	(239)	(445)
Total Securities available for sale, Fair Value	17,614	17,261
U.S. government agencies
Securities
Total Securities available for sale, Amortized Cost	5,664	6,262
Total Securities available for sale, Gross Unrealized Gains	29	31
Total Securities available for sale, Gross Unrealized Losses	(22)	(29)
Total Securities available for sale, Fair Value	5,671	6,264
Corporate
Securities
Total Securities available for sale, Amortized Cost	248,131	241,091
Total Securities available for sale, Gross Unrealized Gains	2,655	2,674
Total Securities available for sale, Gross Unrealized Losses	(3,145)	(2,734)
Total Securities available for sale, Fair Value	247,641	241,031
Mutual funds
Securities
Total Securities available for sale, Amortized Cost	12,669	12,650
Total Securities available for sale, Fair Value	12,669	12,650
Collateralized loan obligations
Securities
Total Securities available for sale, Amortized Cost	256,434	289,349
Total Securities available for sale, Gross Unrealized Gains	7	168
Total Securities available for sale, Gross Unrealized Losses	(350)	(288)
Total Securities available for sale, Fair Value	256,091	289,229
Other
Securities
Total Securities available for sale, Amortized Cost	1,653	1,551
Total Securities available for sale, Fair Value	1,653	1,551
Collateralized Mortgage Backed Securities
Securities
Total Securities available for sale, Amortized Cost	1,088,288	816,089
Total Securities available for sale, Gross Unrealized Gains	4,426	6,066
Total Securities available for sale, Gross Unrealized Losses	(5,466)	(217)
Total Securities available for sale, Fair Value	1,087,248	821,938
REMIC and CMO
Securities
Total Securities available for sale, Amortized Cost	843,561	611,292
Total Securities available for sale, Gross Unrealized Gains	3,258	3,830
Total Securities available for sale, Gross Unrealized Losses	(4,489)	(217)
Total Securities available for sale, Fair Value	842,330	614,905
GNMA
Securities
Total Securities available for sale, Amortized Cost	106,287	60,116
Total Securities available for sale, Gross Unrealized Gains	115	247
Total Securities available for sale, Gross Unrealized Losses	(790)
Total Securities available for sale, Fair Value	105,612	60,363
FNMA
Securities
Securities, held-to-maturity, Amortized Cost	7,812	7,817
Securities held-to-maturity, Net Carrying Amount	7,812	7,817
Securities held-to-maturity, Gross Unrecognized Losses	(609)	(606)
Securities held-to-maturity, fair value	7,203	7,211
Total Securities available for sale, Amortized Cost	63,343	65,446
Total Securities available for sale, Gross Unrealized Gains	243	669
Total Securities available for sale, Gross Unrealized Losses	(120)
Total Securities available for sale, Fair Value	63,466	66,115
FHLMC
Securities
Total Securities available for sale, Amortized Cost	75,097	79,235
Total Securities available for sale, Gross Unrealized Gains	810	1,320
Total Securities available for sale, Gross Unrealized Losses	(67)
Total Securities available for sale, Fair Value	$ 75,840	$ 80,555