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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 | Jun. 30, 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 | $ 1,762,504 | $ 1,719,537
Securities Available for Sale, Gross Unrealized Gains | 40,828 | 2,988
Securities Available for Sale, Gross Unrealized (Losses) | (21,240) | (29,991)
Securities Available for Sale, Estimated Fair Value | 1,782,092 | 1,692,534
Securities Held to Maturity, Amortized Cost | 1,290,572 | 1,335,385
Securities Held to Maturity, Gross Unrealized Gains | 10,408 | 98
Securities Held to Maturity, Gross Unrealized (Losses) | (53,298) | (76,376)
Securities Held to Maturity, Estimated Fair Value | 1,247,682 | 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 | 212,654 | 203,524
Securities Available for Sale, Gross Unrealized Gains | 3,057 | 548
Securities Available for Sale, Gross Unrealized (Losses) | (32) | (1,403)
Securities Available for Sale, Estimated Fair Value | 215,679 | 202,669
Securities Held to Maturity, Amortized Cost | 30,226 | 29,842
Securities Held to Maturity, Gross Unrealized Gains | 157 | 1
Securities Held to Maturity, Gross Unrealized (Losses) | (92) | (522)
Securities Held to Maturity, Estimated Fair Value | 30,291 | 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 | 66,665 | 41,194
Securities Available for Sale, Gross Unrealized Gains | 823 | 0
Securities Available for Sale, Gross Unrealized (Losses) | (1,688) | (2,387)
Securities Available for Sale, Estimated Fair Value | 65,800 | 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 | 36,484 | 31,365
Securities Available for Sale, Gross Unrealized Gains | 434 | 3
Securities Available for Sale, Gross Unrealized (Losses) | (2,848) | (2,957)
Securities Available for Sale, Estimated Fair Value | 34,070 | 28,411
Securities Held to Maturity, Amortized Cost | 14,750 | 16,218
Securities Held to Maturity, Gross Unrealized Gains | 202 | 0
Securities Held to Maturity, Gross Unrealized (Losses) | (783) | (844)
Securities Held to Maturity, Estimated Fair Value | 14,169 | 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 | 1,097,750 | 1,091,122
Securities Available for Sale, Gross Unrealized Gains | 27,544 | 1,610
Securities Available for Sale, Gross Unrealized (Losses) | (16,091) | (22,194)
Securities Available for Sale, Estimated Fair Value | 1,109,203 | 1,070,538
Securities Held to Maturity, Amortized Cost | 398,161 | 423,372
Securities Held to Maturity, Gross Unrealized Gains | 4,468 | 94
Securities Held to Maturity, Gross Unrealized (Losses) | (16,045) | (23,853)
Securities Held to Maturity, Estimated Fair Value | 386,584 | 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 | 109,697 | 123,685
Securities Held to Maturity, Gross Unrealized Gains | 687 | 0
Securities Held to Maturity, Gross Unrealized (Losses) | (6,156) | (8,004)
Securities Held to Maturity, Estimated Fair Value | 104,228 | 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 | 348,951 | 352,332
Securities Available for Sale, Gross Unrealized Gains | 8,970 | 827
Securities Available for Sale, Gross Unrealized (Losses) | (581) | (1,050)
Securities Available for Sale, Estimated Fair Value | 357,340 | 352,109
Securities Held to Maturity, Amortized Cost | 737,738 | 742,268
Securities Held to Maturity, Gross Unrealized Gains | 4,894 | 3
Securities Held to Maturity, Gross Unrealized (Losses) | (30,222) | (43,153)
Securities Held to Maturity, Estimated Fair Value | $ 712,410 | $ 699,118

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