Securities - Schedule of Debt Securities, Available-for-Sale and Held-to-Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Debt securities available-for-sale:
Amortized Cost	$ 762,679	$ 847,272
Gross Unrealized Gains	1,254	1,545
Gross Unrealized Losses	(17,765)	(21,317)
Estimated Fair Value	746,168	827,500
Allowance for Securities Credit Losses	0	0
Debt securities held-to-maturity:
Amortized Cost	1,006,374	1,046,842
Gross Unrealized Gains	1,311	1,019
Gross Unrealized Losses	(81,610)	(94,944)
Estimated Fair Value	926,075	952,917
Allowance for Securities Credit Losses	(898)	(967)	$ (1,058)	$ (1,133)
Total, amortized cost	1,769,053	1,894,114
Total, gross unrealized gains	2,565	2,564
Total, gross unrealized losses	(99,375)	(116,261)
Total, estimated fair value	1,672,243	1,780,417
U.S. government and agency obligations
Debt securities available-for-sale:
Amortized Cost	60,957	62,396
Gross Unrealized Gains	7	11
Gross Unrealized Losses	(4,066)	(5,022)
Estimated Fair Value	56,898	57,385
Allowance for Securities Credit Losses	0	0
Corporate debt securities
Debt securities available-for-sale:
Amortized Cost	17,058	14,042
Gross Unrealized Gains	227	43
Gross Unrealized Losses	(339)	(762)
Estimated Fair Value	16,946	13,323
Allowance for Securities Credit Losses	0	0
Debt securities held-to-maturity:
Amortized Cost	60,520	65,350
Gross Unrealized Gains	421	775
Gross Unrealized Losses	(843)	(1,416)
Estimated Fair Value	60,098	64,709
Allowance for Securities Credit Losses	(675)	(734)
Asset-backed securities
Debt securities available-for-sale:
Amortized Cost	134,266	197,116
Gross Unrealized Gains	61	235
Gross Unrealized Losses	(64)	(84)
Estimated Fair Value	134,263	197,267
Allowance for Securities Credit Losses	0	0
Agency residential
Debt securities available-for-sale:
Amortized Cost	441,549	465,108
Gross Unrealized Gains	956	1,256
Gross Unrealized Losses	(925)	(801)
Estimated Fair Value	441,580	465,563
Allowance for Securities Credit Losses	0	0
Debt securities held-to-maturity:
Amortized Cost	657,881	680,052
Gross Unrealized Gains	699	44
Gross Unrealized Losses	(60,872)	(73,110)
Estimated Fair Value	597,708	606,986
Allowance for Securities Credit Losses	0	0
Agency commercial
Debt securities available-for-sale:
Amortized Cost	108,849	108,610
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(12,371)	(14,648)
Estimated Fair Value	96,481	93,962
Allowance for Securities Credit Losses	0	0
Debt securities held-to-maturity:
Amortized Cost	79,514	79,925
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(5,172)	(5,878)
Estimated Fair Value	74,344	74,048
Allowance for Securities Credit Losses	0	0
State and municipal debt obligations
Debt securities held-to-maturity:
Amortized Cost	189,349	201,369
Gross Unrealized Gains	189	199
Gross Unrealized Losses	(14,172)	(13,665)
Estimated Fair Value	175,366	187,903
Allowance for Securities Credit Losses	(29)	(31)
Non-agency commercial
Debt securities held-to-maturity:
Amortized Cost	19,110	20,146
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(551)	(875)
Estimated Fair Value	18,559	19,271
Allowance for Securities Credit Losses	(194)	(202)
Total mortgage-backed securities
Debt securities available-for-sale:
Amortized Cost	550,398	573,718
Gross Unrealized Gains	959	1,256
Gross Unrealized Losses	(13,296)	(15,449)
Estimated Fair Value	538,061	559,525
Allowance for Securities Credit Losses	0	0
Debt securities held-to-maturity:
Amortized Cost	756,505	780,123
Gross Unrealized Gains	701	45
Gross Unrealized Losses	(66,595)	(79,863)
Estimated Fair Value	690,611	700,305
Allowance for Securities Credit Losses	$ (194)	$ (202)

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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