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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 | 6 Months Ended | 12 Months Ended
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Jun. 30, 2025 | Dec. 31, 2024
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |
Estimated Fair Value, Less than 12 Months | $ 462,771 | $ 1,324,604
Gross Unrealized (Losses), Less than 12 Months | (7,986) | (18,989)
Estimated Fair Value, 12 Months or More | 1,130,887 | 1,148,537
Gross Unrealized (Losses), 12 Months or More | (66,552) | (87,378)
Estimated Fair Value, Total | 1,593,658 | 2,473,141
Gross Unrealized (Losses), Total | (74,538) | (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 | 60,071 | 123,277
Gross Unrealized (Losses), Less than 12 Months | (124) | (1,925)
Estimated Fair Value, 12 Months or More | 0 | 0
Gross Unrealized (Losses), 12 Months or More | 0 | 0
Estimated Fair Value, Total | 60,071 | 123,277
Gross Unrealized (Losses), Total | (124) | (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 | 41,787 | 38,807
Gross Unrealized (Losses), Less than 12 Months | (1,688) | (2,387)
Estimated Fair Value, 12 Months or More | 0 | 0
Gross Unrealized (Losses), 12 Months or More | 0 | 0
Estimated Fair Value, Total | 41,787 | 38,807
Gross Unrealized (Losses), Total | (1,688) | (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 | 17,977 | 15,802
Gross Unrealized (Losses), Less than 12 Months | (202) | (293)
Estimated Fair Value, 12 Months or More | 30,256 | 27,803
Gross Unrealized (Losses), 12 Months or More | (3,429) | (3,508)
Estimated Fair Value, Total | 48,233 | 43,605
Gross Unrealized (Losses), Total | (3,631) | (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 | 339,853 | 981,747
Gross Unrealized (Losses), Less than 12 Months | (5,930) | (13,848)
Estimated Fair Value, 12 Months or More | 220,455 | 237,487
Gross Unrealized (Losses), 12 Months or More | (26,206) | (32,199)
Estimated Fair Value, Total | 560,308 | 1,219,234
Gross Unrealized (Losses), Total | (32,136) | (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 | 106,057 | 115,681
Gross Unrealized (Losses), 12 Months or More | (6,156) | (8,004)
Estimated Fair Value, Total | 106,057 | 115,681
Gross Unrealized (Losses), Total | (6,156) | (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 | 3,083 | 164,971
Gross Unrealized (Losses), Less than 12 Months | (42) | (536)
Estimated Fair Value, 12 Months or More | 774,119 | 767,566
Gross Unrealized (Losses), 12 Months or More | (30,761) | (43,667)
Estimated Fair Value, Total | 777,202 | 932,537
Gross Unrealized (Losses), Total | $ (30,803) | $ (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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- Definition This item represents the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized as available-for-sale and held-to-maturity securities. + References No definition available. + Details
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