Loans Receivable - Summary of Allowance for Loan Losses On Loans Receivables (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Allowance for loan losses:
Beginning balance	$ 16,507	$ 16,654	$ 16,461	$ 16,620
Non-purchased credit deteriorated loans	1,707		1,700
CECL adoption			(301)
CECL day 1 provision			1,707
Purchased credit deteriorated loans	601		601
Provision	996	0	1,340	0
Charge-offs	(1,868)	(200)	(1,868)	(200)
Recoveries	27	212	30	246
Total	17,970	16,666	17,970	16,666
Individually evaluated for impairment	0		0		$ 118
Collectively evaluated for impairment	17,970		17,970		16,343
Loans:
Individually evaluated for impairment	9,753		9,753		12,377
Collectively evaluated for impairment	1,491,111		1,491,111		1,360,447
Ending balance	1,500,864		1,500,864		1,372,824
Commercial real estate [Member]
Allowance for loan losses:
Beginning balance	10,037	7,088	8,654	7,458
Non-purchased credit deteriorated loans	1,586
CECL adoption			1,384
CECL day 1 provision			1,586
Purchased credit deteriorated loans	498		498
Provision	1,697	1,583	1,693	1,179
Charge-offs	(1,718)	(200)	(1,718)	(200)
Recoveries	23	212	26	246
Total	12,123	8,683	12,123	8,683
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	12,123		12,123		8,654
Loans:
Individually evaluated for impairment	4,485		4,485		12,030
Collectively evaluated for impairment	1,018,469		1,018,469		861,543
Ending balance	1,022,954		1,022,954		873,573
Commercial and industrial [Member]
Allowance for loan losses:
Beginning balance	214	266	271	713
Non-purchased credit deteriorated loans	105
CECL adoption			(73)
CECL day 1 provision			105
Purchased credit deteriorated loans	103		103
Provision	(19)	13	(3)	(434)
Charge-offs	0	0	0	0
Recoveries	4	0	4	0
Total	407	279	407	279
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	407		407		271
Loans:
Individually evaluated for impairment	2,232		2,232		10
Collectively evaluated for impairment	43,790		43,790		28,849
Ending balance	46,022		46,022		28,859
Construction [Member]
Allowance for loan losses:
Beginning balance	5,349	8,034	6,289	7,228
Non-purchased credit deteriorated loans	0
CECL adoption			(1,269)
CECL day 1 provision			0
Purchased credit deteriorated loans	0		0
Provision	(672)	(1,604)	(343)	(798)
Charge-offs	(148)	0	(148)	0
Recoveries	0	0	0	0
Total	4,529	6,430	4,529	6,430
Individually evaluated for impairment	0		0		118
Collectively evaluated for impairment	4,529		4,529		6,171
Loans:
Individually evaluated for impairment	2,925		2,925		148
Collectively evaluated for impairment	380,690		380,690		417,390
Ending balance	383,615		383,615		417,538
Residential first-lien mortgage [Member]
Allowance for loan losses:
Beginning balance	654	262	236	267
Non-purchased credit deteriorated loans	16
CECL adoption			428
CECL day 1 provision			16
Purchased credit deteriorated loans	0		0
Provision	(7)	(3)	(17)	(8)
Charge-offs	(2)	0	(2)	0
Recoveries	0	0	0	0
Total	661	259	661	259
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	661		661		236
Loans:
Individually evaluated for impairment	111		111		118
Collectively evaluated for impairment	40,133		40,133		43,007
Ending balance	40,244		40,244		43,125
Home equity/consumer [Member]
Allowance for loan losses:
Beginning balance	253	46	45	48
Non-purchased credit deteriorated loans	0
CECL adoption			195
CECL day 1 provision			0
Purchased credit deteriorated loans	0		0
Provision	(3)	4	10	2
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Total	250	50	250	50
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	250		250		45
Loans:
Individually evaluated for impairment	0		0		71
Collectively evaluated for impairment	8,029		8,029		9,658
Ending balance	8,029		8,029		9,729
PPP [Member]
Allowance for loan losses:
Beginning balance				0
Provision				0
Charge-offs				0
Recoveries				0
Total		0		0
Unallocated [Member]
Allowance for loan losses:
Beginning balance	0	958	966	906
Non-purchased credit deteriorated loans	0
CECL adoption			(966)
CECL day 1 provision			0
Purchased credit deteriorated loans	0		0
Provision	0	7	0	59
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Total	0	$ 965	0	$ 965
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		966
Loans:
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Ending balance	$ 0		$ 0		$ 0