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Securities Available for Sale and Held to Maturity - Securities Held to Maturity by Credit Rating, as Determined by Moody's (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] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 1,290,572 | $ 1,335,385
Aaa [Member] |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 53,200 | 1,335,385
Aa1 to Aa3 [Member] |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 1,237,372 | $ 0

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