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Securities - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items] |  |  |
Realized gains on sales |  | $ 9.3 | $ 11.8
Investments pledged, carrying value | $ 134.8 | $ 115.0 |
Minimum [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Underwater security | 10 years |  |
Loss position existed | 3 years |  |

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- Definition Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References No definition available. + Details
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