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Investment Securities - Proceeds from Sale, Gross Gains (Losses) Realized on Sales, Maturities and Other-Than-Temporary Impairment Charges Related to Securities Available for Sale (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Gain (Loss) on Securities [Line Items] |  |  |
Proceeds from sale | $ 33,756 | $ 0 | $ 0
Debt Securities, Realized Gain (Loss), Total | (103) | 2 | 16
Calls And Maturities [Member] |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Gross gains | 0 | 2 | 16
Gross Losses | 0 | 0 | 0
Debt Securities, Realized Gain (Loss), Total | 0 | 2 | 16
Sales [Member] |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Gross gains | 0 | 0 | 0
Gross Losses | 103 | 0 | 0
Debt Securities, Realized Gain (Loss), Total | $ 103 | $ 0 | $ 0

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- Definition Amount of realized gain (loss) on 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/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 + Details
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