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Investment Securities - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 USD ($) Security | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |
Securities available for sale |  | $ 1,041,380 |
Other investments | $ 25,200 | 11,700 |
Provision for Other Credit Losses | 0 | 0 | $ 0
Equity Securities, FV-NI | $ 1,200 |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security | 209 |  |
Equity Securities, FV-NI, Gain (Loss) | $ 0 | 0 |
Total debt securities, Amortized Cost | 898,702 | 1,045,579 |
Debt Securities, Available-for-Sale | 762,661 | 1,041,380 |
Obligations of U.S. Government-Sponsored Enterprises [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Total debt securities, Amortized Cost | 527,800 |  |
Debt Securities, Available-for-Sale | 449,000 |  |
Held-to-maturity Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Deposit Liabilities, Collateral Issued, Financial Instruments | 368,800 | 313,900 |
Available-for-sale Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Deposit Liabilities, Collateral Issued, Financial Instruments | 626,700 | 759,100 |
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Total debt securities, Amortized Cost | 527,777 | 632,687 |
Debt Securities, Available-for-Sale | 448,989 | 629,974 |
Corporate Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Total debt securities, Amortized Cost | 32,010 | 32,088 |
Debt Securities, Available-for-Sale | 29,204 | 32,949 |
Sales [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Gains | 0 | 0 | 0
Calls And Maturities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Gains | $ 2 | $ 16 | $ 70

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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