Loans and ACL - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023 USD ($) Loan	Dec. 31, 2022 USD ($) Loan
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 2,457,325	$ 2,412,699
Interest Income on NonAccrual Loans	$ 378
Number of doubtful loans \| Loan	0	0
Loans pledged	$ 2,457,325
Nonperforming trouble debt restructuring		$ 1,100
Amortized Cost of PCD Loans	58,200
Non-Credit Discount on PCD Loans	5,300
Mortgage loans with amortized cost	645	0
Amortized cost of ACL related to PCD loans	639
Risk Grade 7
Loans and Leases Receivable Disclosure [Line Items]
Gross loans		58,404
Loans pledged	79,171
Grade 5 Pass/Watch [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans		143,207
Paycheck Protection Plan Liquidity Facility Advances [Member] \| Asset Pledged as Collateral without Right [Member] \| Federal Home Loan Bank Advances [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans pledged	$ 0	51
Minimum [Member] \| Grade 5 Pass/Watch [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loan To Value Ratio	90.00%
Commercial and Residential Mortgages [Member] \| Asset Pledged as Collateral without Right [Member] \| Federal Home Loan Bank Advances [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans pledged	$ 531,800	436,000
Paycheck Protection Program [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	7,988	$ 11,967
Loans pledged	$ 7,988

Amortized cost of ACL Related To PCD Loans

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Amortized cost of PCD loans

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Interest income on nonaccrual loans.

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Loan to value ratio.

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mortgage loans with an amortized cost.

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Non-credit discount on PCD loans.

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Number of doubtful loans.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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