Loans - Additional Information (Detail)	12 Months Ended
Dec. 31, 2022 USD ($) Number Loan	Dec. 31, 2021 USD ($) Loan Number	Dec. 31, 2020 USD ($)
Loans outstanding	$ 4,443,000	$ 4,849,000	$ 5,279,000
Loan balance	$ 189,000	$ 195,000
Number of Loans \| Loan	0	1
Allowance for loan losses includes specific reserve for TDR	$ 0	$ 0
Residential Real Estate [Member]
Loans collateralized by real estate	$ 0	$ 0
Paycheck Protection Program [Member]
CARES Act number of guaranteed loans \| Number	0	134
CARES Act aggregate guaranteed outstanding loans	$ 0	$ 13,100,000
Paycheck Protection Program [Member] \| Commercial and Industrial Loans [Member]
CARES Act aggregate guaranteed outstanding loans	$ 0	$ 5,500,000

Allowance for loan losses includes specific reserve for troubled debt restructurings.

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CARES Act aggregate guaranteed outstanding loans.

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CARES Act number of guaranteed loans.

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- Definition

Loans collaterized by real estate properties..

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Number of financing receivables that have been modified by troubled debt restructurings.

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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