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Securities Available for Sale and Held to Maturity - Amortized Cost and Estimated Fair Value of Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 1,842,444	$ 1,719,537
Securities Available for Sale, Gross Unrealized Gains	48,915	2,988
Securities Available for Sale, Gross Unrealized (Losses)	(14,529)	(29,991)
Securities Available for Sale, Estimated Fair Value	1,876,830	1,692,534
Securities Held to Maturity, Amortized Cost	1,207,454	1,335,385
Securities Held to Maturity, Gross Unrealized Gains	2,350	98
Securities Held to Maturity, Gross Unrealized (Losses)	(29,235)	(76,376)
Securities Held to Maturity, Estimated Fair Value	1,180,569	1,259,107
U.S. Treasury Securities [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	205,282	203,524
Securities Available for Sale, Gross Unrealized Gains	3,666	548
Securities Available for Sale, Gross Unrealized (Losses)	0	(1,403)
Securities Available for Sale, Estimated Fair Value	208,948	202,669
Securities Held to Maturity, Amortized Cost	30,615	29,842
Securities Held to Maturity, Gross Unrealized Gains	185	1
Securities Held to Maturity, Gross Unrealized (Losses)	0	(522)
Securities Held to Maturity, Estimated Fair Value	30,800	29,321
U.S. Government Agency Obligations [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	70,924	41,194
Securities Available for Sale, Gross Unrealized Gains	609	0
Securities Available for Sale, Gross Unrealized (Losses)	(684)	(2,387)
Securities Available for Sale, Estimated Fair Value	70,849	38,807
Securities Held to Maturity, Amortized Cost	0	0
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	0	0
Securities Held to Maturity, Estimated Fair Value	0	0
Residential Mortgage Pass-Through Securities Guaranteed by GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	40,425	31,365
Securities Available for Sale, Gross Unrealized Gains	106	3
Securities Available for Sale, Gross Unrealized (Losses)	(1,996)	(2,957)
Securities Available for Sale, Estimated Fair Value	38,535	28,411
Securities Held to Maturity, Amortized Cost	13,154	16,218
Securities Held to Maturity, Gross Unrealized Gains	22	0
Securities Held to Maturity, Gross Unrealized (Losses)	(393)	(844)
Securities Held to Maturity, Estimated Fair Value	12,783	15,374
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	1,165,292	1,091,122
Securities Available for Sale, Gross Unrealized Gains	33,836	1,610
Securities Available for Sale, Gross Unrealized (Losses)	(11,369)	(22,194)
Securities Available for Sale, Estimated Fair Value	1,187,759	1,070,538
Securities Held to Maturity, Amortized Cost	372,311	423,372
Securities Held to Maturity, Gross Unrealized Gains	2,070	94
Securities Held to Maturity, Gross Unrealized (Losses)	(7,812)	(23,853)
Securities Held to Maturity, Estimated Fair Value	366,569	399,613
Other Residential Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	0	0
Securities Available for Sale, Gross Unrealized Gains	0	0
Securities Available for Sale, Gross Unrealized (Losses)	0	0
Securities Available for Sale, Estimated Fair Value	0	0
Securities Held to Maturity, Amortized Cost	96,667	123,685
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	(4,233)	(8,004)
Securities Held to Maturity, Estimated Fair Value	92,434	115,681
Commercial Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	360,521	352,332
Securities Available for Sale, Gross Unrealized Gains	10,698	827
Securities Available for Sale, Gross Unrealized (Losses)	(480)	(1,050)
Securities Available for Sale, Estimated Fair Value	370,739	352,109
Securities Held to Maturity, Amortized Cost	694,707	742,268
Securities Held to Maturity, Gross Unrealized Gains	73	3
Securities Held to Maturity, Gross Unrealized (Losses)	(16,797)	(43,153)
Securities Held to Maturity, Estimated Fair Value	$ 677,983	$ 699,118

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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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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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