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Investment Securities - Narratives (Details) | Jun. 30, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
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Investment Securities |  |
Number of securities in a continuous loss position | 105 | 80
Percentage of individual securities' amortized cost basis | 10.40% | 9.90%
Percentage of total amortized cost basis of the investment securities portfolio | 6.40% | 8.70%
Number of securities in a continuous loss position for over 12 months | 56 | 57
Number of securities | 105 | 80
Allowance for credit losses for available-for-sale securities | $ | $ 0 | $ 0

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