Loans - Summary of Activity in Allowance for Loan and Lease Losses and Allowance for Credit Losses for Unfunded Loan Commitments (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance		$ 3,679	$ 3,693	$ 3,734	$ 3,203
Provision for credit losses		75	75	150	150
CECL Adoption Adjustment	[1]				412
Loans charged-off		(2)	(1)	(3)	(7)
Recoveries of loans previously charged off		103	9	117	18
Ending balance		3,871	3,643	3,871	3,643
Total Allowance for credit losses for loans and unfunded loan commitments		4,873	4,441	4,873	4,441
Unfunded Loan Commitments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	[2]	1,018	665	875	0
Provision for credit losses	[2]	(16)	133	127	133
CECL Adoption Adjustment	[1],[2]				665
Ending balance	[2]	1,002	798	1,002	798
Allowance for Credit Losses for Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Provision for credit losses		91	(58)	23	17
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance		2,649	2,669	2,693	1,944
CECL Adoption Adjustment	[1]				666
Loans charged-off		0	0	0	0
Recoveries of loans previously charged off		99	5	104	10
Ending balance		2,814	2,632	2,814	2,632
Total Allowance for credit losses for loans and unfunded loan commitments		3,786	3,403	3,786	3,403
Commercial [Member] | Unfunded Loan Commitments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	[2]	987	640	847	0
Provision for credit losses	[2]	(15)	131	125	131
CECL Adoption Adjustment	[1],[2]				640
Ending balance	[2]	972	771	972	771
Commercial [Member] | Allowance for Credit Losses for Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Provision for credit losses		66	(42)	17	12
Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance		839	848	849	752
CECL Adoption Adjustment	[1]				75
Loans charged-off		0	0	0	0
Recoveries of loans previously charged off		0	0	6	0
Ending balance		860	831	860	831
Total Allowance for credit losses for loans and unfunded loan commitments		890	858	890	858
Residential [Member] | Unfunded Loan Commitments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	[2]	31	25	28	0
Provision for credit losses	[2]	(1)	2	2	2
CECL Adoption Adjustment	[1],[2]				25
Ending balance	[2]	30	27	30	27
Residential [Member] | Allowance for Credit Losses for Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Provision for credit losses		21	(17)	5	4
Consumer [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance		191	176	192	507
CECL Adoption Adjustment	[1]				(329)
Loans charged-off		(2)	(1)	(3)	(7)
Recoveries of loans previously charged off		4	4	7	8
Ending balance		197	180	197	180
Total Allowance for credit losses for loans and unfunded loan commitments		197	180	197	180
Consumer [Member] | Unfunded Loan Commitments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	[2]	0	0	0	0
Provision for credit losses	[2]	0	0	0	0
CECL Adoption Adjustment	[1],[2]				0
Ending balance	[2]	0	0	0	0
Consumer [Member] | Allowance for Credit Losses for Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Provision for credit losses		$ 4	$ 1	$ 1	$ 1

[1] On January 1, 2023, the Company adopted ASU 2016-13 ("CECL"). See Note 2 for additional information regarding the adoption of ASU 2016-13.

[2] The allowance for credit losses for unfunded loan commitments is included in other liabilities on the Company's Consolidated Balance Sheets.