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Securities Available for Sale and Held to Maturity - Securities with Gross Unrealized Losses, Segregated by Length of Impairment (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months | $ 101,060 | $ 1,324,604
Gross Unrealized (Losses), Less than 12 Months | (266) | (18,989)
Estimated Fair Value, 12 Months or More | 1,104,931 | 1,148,537
Gross Unrealized (Losses), 12 Months or More | (43,498) | (87,378)
Estimated Fair Value, Total | 1,205,991 | 2,473,141
Gross Unrealized (Losses), Total | (43,764) | (106,367)
US Treasury Securities [Member] |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months |  | 123,277
Gross Unrealized (Losses), Less than 12 Months |  | (1,925)
Estimated Fair Value, 12 Months or More |  | 0
Gross Unrealized (Losses), 12 Months or More |  | 0
Estimated Fair Value, Total |  | 123,277
Gross Unrealized (Losses), Total |  | (1,925)
U.S. Government Agency Obligations [Member] |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months | 3,905 | 38,807
Gross Unrealized (Losses), Less than 12 Months | (14) | (2,387)
Estimated Fair Value, 12 Months or More | 40,952 | 0
Gross Unrealized (Losses), 12 Months or More | (670) | 0
Estimated Fair Value, Total | 44,857 | 38,807
Gross Unrealized (Losses), Total | (684) | (2,387)
Residential Mortgage Pass-Through Securities Guaranteed by GNMA [Member] |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months | 5,925 | 15,802
Gross Unrealized (Losses), Less than 12 Months | (18) | (293)
Estimated Fair Value, 12 Months or More | 26,946 | 27,803
Gross Unrealized (Losses), 12 Months or More | (2,371) | (3,508)
Estimated Fair Value, Total | 32,871 | 43,605
Gross Unrealized (Losses), Total | (2,389) | (3,801)
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member] |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months | 91,230 | 981,747
Gross Unrealized (Losses), Less than 12 Months | (234) | (13,848)
Estimated Fair Value, 12 Months or More | 205,163 | 237,487
Gross Unrealized (Losses), 12 Months or More | (18,947) | (32,199)
Estimated Fair Value, Total | 296,393 | 1,219,234
Gross Unrealized (Losses), Total | (19,181) | (46,047)
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] |  |
Estimated Fair Value, Less than 12 Months | 0 | 0
Gross Unrealized (Losses), Less than 12 Months | 0 | 0
Estimated Fair Value, 12 Months or More | 92,434 | 115,681
Gross Unrealized (Losses), 12 Months or More | (4,233) | (8,004)
Estimated Fair Value, Total | 92,434 | 115,681
Gross Unrealized (Losses), Total | (4,233) | (8,004)
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] |  |
Estimated Fair Value, Less than 12 Months | 0 | 164,971
Gross Unrealized (Losses), Less than 12 Months | 0 | (536)
Estimated Fair Value, 12 Months or More | 739,436 | 767,566
Gross Unrealized (Losses), 12 Months or More | (17,277) | (43,667)
Estimated Fair Value, Total | 739,436 | 932,537
Gross Unrealized (Losses), Total | $ (17,277) | $ (44,203)

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- Definition This item represents the aggregate fair value of investments categorized as available-for-sale and held-to-maturity securities that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities that have been in a loss position for twelve months or longer for those securities which are categorized as available-for-sale and held-to-maturity securities. + References No definition available. + Details
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