Fair Value Disclosures - Additional Information (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) Loans	Mar. 31, 2023 USD ($) Loans	Dec. 31, 2023 USD ($) Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets transfer between Level 2 and Level 3	$ 0	$ 0	$ 0
Other real estate owned, total	937,000	175,000	$ 483,000
Real state owned	454,000	175,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real state owned	$ 0	$ 0
Residential Mortgage [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans held-for-sale | Loans	0	0	0
Recognized credit losses	$ 0	$ 0
Minimum [Member] | Measurement Input, Discount Rate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt discounts, percentage	5
Maximum [Member] | Measurement Input, Discount Rate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt discounts, percentage	25