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v3.23.3

Investment Securities - Additional Information (Detail) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($)
Debt Securities, Held-to-maturity, Restricted | $ 119,200,000 |  | $ 368,800,000
Debt Securities, Available-for-sale, Restricted | $ 377,600,000 |  | 626,700,000
Investment Securities in Unrealized Loss Position, Qualitative Disclosure, Number of Positions, Total | 231 |  |
Other Investments and Securities, at Cost | $ 6,200,000 |  | 1,200,000
Federal Home Loan Bank Stock | 42,800,000 |  | 25,200,000
Amortized Cost | 978,690,000 |  | 898,702,000
Debt Securities, Available-for-Sale | 817,603,000 |  | 762,661,000
Sales |  |  |
Gross Losses | 103,000 | $ 0 |
Gross Gains | $ 0 | 0 |
US Government-sponsored Enterprises Debt Securities [Member] |  |  |
Percent of Unrealized Losses | 96.00% |  |
Amortized Cost | $ 1,000,000 |  | 1,000,000
Debt Securities, Available-for-Sale | $ 887,000 |  | $ 882,000
Corporate Debt Securities [Member] |  |  |
Investment Securities in Unrealized Loss Position, Qualitative Disclosure, Number of Positions, Total | 8 |  | 6
Amortized Cost | $ 33,752,000 |  | $ 32,010,000
Debt Securities, Available-for-Sale | 29,468,000 |  | $ 29,204,000
Equity Securities [Member] |  |  |
Equity Securities without Readily Determinable Fair Value, Impairment Loss, Annual Amount | $ 0 | $ 0 |

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + 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)) -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 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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