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Securities - Additional Information (Detail) - USD ($) | 9 Months Ended
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Sep. 30, 2023 | Sep. 30, 2022
Debt Securities, Available-for-Sale [Line Items] |  |
Sale of low yielding securities |  | $ 226,000,000
Debt securities. average yield percentage |  | 0.16%
Reinvested in debt securities |  | $ 220,000,000
Reinvested debt securities, average yield percentage |  | 1.86%
Proceeds from sales of available for sale securities | $ 0 | $ 222,474,000
Avaliable for sale of debt securities realized gains or losses | $ 0 |

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 + Details
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