Commitments and Contingent Liabilities - Additional Information (Detail) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Notional Amount Of Performance Standby Letters Of Credit	$ 500,000
Notional Amount Of Commercial Letters Of Credit	0
Notional Amount Of Financial Standby Letters Of Credit	100,000
Financial instrument of credit risk	100,000	$ 100,000
Financial instrument of credit risk	100,000	100,000
Unfunded commitment liability	5,500,000	$ 7,400,000
Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	0
Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 1,000,000