Borrowing Arrangements - Additional Information (Detail) - USD ($)		3 Months Ended
	Aug. 17, 2021	Mar. 31, 2024	Dec. 31, 2023	Dec. 29, 2023	Sep. 30, 2020
Short-term Debt [Line Items]
FHLB Advance, Collateral Pledged		$ 397,000,000	$ 401,400,000
FHLB Advance, Available Borrowing Capacity		351,500,000	280,900,000
FHLB Advance, Amount Of Advances				$ 75,000,000
FHLB Advance, Interest Rate				5.70%
Junior Subordinated debt securities		$ 54,326,000	54,291,000
Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, IssuanceDate		Sep. 30, 2020
Debt Instrument, Interest Rate Terms		The subordinated debt has a fixed interest rate of 5.00% for the first 5 years
SOFR [Member] | Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis		variable rate equal to then current three-month term Secured Overnight Financing Rate (“SOFR”) plus 0.488%.
Debt Instrument, Variable Rate		0.488%
Debt Instrument, Face Amount					$ 20,000,000
Debt Instrument, Fixed Interest Rate					5.00%
Related issuance costs		$ 300,000
Junior Subordinated debt securities		$ 20,000,000	20,000,000
SOFR [Member] | Additional Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis		variable rate equal to then current three-month term SOFR plus 0.286%
Debt Instrument, Variable Rate		3.50%
Debt Instrument, Face Amount	$ 35,000,000
Debt Instrument, Interest Rate Terms		The subordinated debt has a fixed interest rate of 3.50%
Related issuance costs	$ 760,000
Junior Subordinated debt securities		$ 35,000,000	35,000,000
Debt Instrument, Maturity Date	Sep. 01, 2031
Correspondent Banks [Member]
Short-term Debt [Line Items]
Borrowings outstanding		0	0
Line Of Credit Maximum Borrowing Capacity		123,000,000
Secured Debt [Member] | Federal Reserve Bank of San Francisco [Member]
Short-term Debt [Line Items]
Loans Pledged As Collateral		410,500,000	432,500,000
Line Of Credit Available Borrowing Capacity		334,300,000	343,300,000
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Borrowings outstanding		0	$ 0
Line Of Credit Maximum Borrowing Capacity		$ 3,000,000
Revolving Credit Facility [Member] | One Year Prime Rate [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis		one-year term at a rate of Prime plus 0.40%
Debt Instrument, Variable Rate		0.40%