Loans - Additional Information (Detail)	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) Number Loan
Number of Loans \| Loan		1
Loan balance	$ 194,000	$ 195,000
Allowance for loan losses includes specific reserve for TDR	0	0
Loans outstanding	4,700,000	4,800,000
Residential Real Estate [Member]
Loans collateralized by real estate	0	$ 0
Paycheck Protection Program [Member]
CARES Act number of guaranteed loans \| Number		134
CARES Act aggregate guaranteed outstanding loans		$ 13,100,000
Paycheck Protection Program [Member] \| Commercial and Industrial Loans [Member]
CARES Act aggregate guaranteed outstanding loans	$ 3,200,000	$ 5,500,000

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

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- Definition

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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