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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
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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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