Investment Securities - Additional Information (Detail) $ in Thousands	12 Months Ended
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

This item represents the gross gain on maturities of available for sale securities.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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