Delinquency status of loans and leases receivable modified past due ninety days or more.

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Delinquency status of loans and leases receivable modified past due thirty to eighty nine days.

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Financing receivable recorded investment accrual or nonaccrual status.

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Loans and leases receivable.

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Loans and leases weighted-average remaining term

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Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed.

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Residential mortgage loans secured by residential real estate in process of foreclosure.

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Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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Loans and Leases and the Allowance for Credit Losses - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Loans And Leases Receivable [Line Items]
Modified in period	$ 441,000	$ 348,000	$ 916,000	$ 641,000
Amount of foreclosed residential real estate property held	33,000		33,000		$ 39,000
Loans secured by residential real estate that were in the process of foreclosure	$ 165,000		$ 165,000		170,000
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed	39.00%		39.00%
Guaranteed by Government-Related Entities
Loans And Leases Receivable [Line Items]
Modified in period	$ 47,000	25,000	$ 88,000	48,000
Modified past due 30-89 days	45,000	11,000	45,000	11,000
Modified past due 90 days or more	$ 27,000	$ 4,000	$ 27,000	$ 4,000
Commercial Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	7 months 6 days	1 year	9 months 18 days	1 year 1 month 6 days
Commercial Real Estate \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 15,800,000		$ 15,800,000
Commercial Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					16,400,000
Residential Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	8 years 10 months 24 days	8 years 7 months 6 days	10 years 2 months 12 days	8 years 10 months 24 days
Residential Real Estate \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 18,600,000		$ 18,600,000
Residential Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					18,800,000
Commercial and industrial
Loans And Leases Receivable [Line Items]
Modified in period	$ 64,000	$ 27,000	$ 209,000	$ 95,000
Weighted-average remaining term	8 months 12 days	1 year 3 months 18 days	9 months 18 days	1 year 3 months 18 days
Commercial and industrial \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 19,100,000		$ 19,100,000
Commercial and industrial \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					13,400,000
Commercial \| Commercial Real Estate
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	168,000		168,000		189,000
Modified in period	168,000	$ 60,000	377,000	$ 150,000
Residential \| Residential Real Estate
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	209,000		209,000		190,000
Modified in period	56,000	39,000	101,000	72,000
Commercial Loans and Commercial Real Estate \| Minimum
Loans And Leases Receivable [Line Items]
Amount of real estate loan as reported as accruing or nonaccruing	5,000		5,000
Unfunded Loan Commitment
Loans And Leases Receivable [Line Items]
Modified in period	1,000	78,000	27,000	82,000
Home equity lines and loans \| Consumer:
Loans And Leases Receivable [Line Items]
Modified in period	0	1,000	1,000	1,000
Home equity lines and loans \| Consumer: \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss	2,600,000		2,600,000
Home equity lines and loans \| Consumer: \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					2,600,000
Other \| Consumer:
Loans And Leases Receivable [Line Items]
Modified in period	0	$ 0	0	$ 0
Other \| Consumer: \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 10,300,000		$ 10,300,000
Other \| Consumer: \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					$ 11,000,000