Loans Receivable - Summary of loans by year of origination, internally assigned credit grades and risk characteristics (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 1,842,045	$ 1,821,274
Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current period gross charge-offs Prior	9,950	236
Current period gross charge-offs Total	9,950	236
Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current period gross charge-offs Prior	83	516
Current period gross charge-offs Total	83	516
Construction Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current period gross charge-offs Prior		0
Current period gross charge-offs Total		0
Loans Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	78,943	163,048
2024 and 2023	172,781	196,821
2023 and 2022	187,571	374,177
2022 and 2021	332,820	246,667
2021 and 2020	182,204	84,984
Prior	662,550	628,254
Revolving Loans	225,176	127,323
Total	1,842,045	1,821,274
Loans Receivable [Member] \| Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	48,349	143,453
2024 and 2023	129,926	168,828
2023 and 2022	163,654	309,379
2022 and 2021	302,928	136,509
2021 and 2020	131,269	65,693
Prior	596,171	558,623
Revolving Loans	6,030	2,600
Total	1,378,327	1,385,085
Loans Receivable [Member] \| Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	2,641	0
2024 and 2023	3,046	3,022
2023 and 2022	4,952	10,876
2022 and 2021	10,625	11,183
2021 and 2020	11,517	0
Prior	16,224	19,633
Revolving Loans	29,404	48,143
Total	78,409	92,857
Loans Receivable [Member] \| Construction Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	18,602	17,765
2024 and 2023	4,000	22,109
2023 and 2022	7,234	46,558
2022 and 2021	9,380	92,841
2021 and 2020	31,349	16,431
Prior	6,416	242
Revolving Loans	178,354	61,223
Total	255,335	257,169
Loans Receivable [Member] \| Residential First lien Mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	5,204	596
2024 and 2023	34,213	1,895
2023 and 2022	11,357	6,789
2022 and 2021	7,957	6,134
2021 and 2020	7,083	2,860
Prior	42,744	49,756
Revolving Loans	0	0
Total	108,558	68,030
Loans Receivable [Member] \| Residential First lien Mortgage [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	5,204	596
2024 and 2023	34,213	1,895
2023 and 2022	11,357	6,789
2022 and 2021	7,957	6,134
2021 and 2020	7,083	2,860
Prior	42,597	49,662
Revolving Loans	0	0
Total	108,411	67,936
Loans Receivable [Member] \| Residential First lien Mortgage [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	147	94
Revolving Loans	0	0
Total	147	94
Loans Receivable [Member] \| Home Equity Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	4,147	1,234
2024 and 2023	1,596	967
2023 and 2022	374	575
2022 and 2021	1,930	0
2021 and 2020	986	0
Prior	995	0
Revolving Loans	11,388	15,357
Total	21,416	18,133
Loans Receivable [Member] \| Home Equity Loan [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	4,147	1,234
2024 and 2023	1,596	967
2023 and 2022	374	556
2022 and 2021	1,930	0
2021 and 2020	986	0
Prior	995	0
Revolving Loans	11,388	15,357
Total	21,416	18,114
Loans Receivable [Member] \| Home Equity Loan [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	19
2022 and 2021	0	0
2021 and 2020	0	0
Prior	0	0
Revolving Loans	0	0
Total	0	19
Loans Receivable [Member] \| Pass [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	78,943	163,048
2024 and 2023	172,781	196,821
2023 and 2022	187,571	374,158
2022 and 2021	332,820	246,667
2021 and 2020	182,204	78,046
Prior	636,877	603,876
Revolving Loans	225,176	127,323
Total	1,816,372	1,789,939
Loans Receivable [Member] \| Pass [Member] \| Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	48,349	143,453
2024 and 2023	129,926	168,828
2023 and 2022	163,654	309,379
2022 and 2021	302,928	136,509
2021 and 2020	131,269	58,755
Prior	572,356	537,532
Revolving Loans	6,030	2,600
Total	1,354,512	1,357,056
Loans Receivable [Member] \| Pass [Member] \| Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	2,641	0
2024 and 2023	3,046	3,022
2023 and 2022	4,952	10,876
2022 and 2021	10,625	11,183
2021 and 2020	11,517	0
Prior	14,513	16,440
Revolving Loans	29,404	48,143
Total	76,698	89,664
Loans Receivable [Member] \| Pass [Member] \| Construction Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	18,602	17,765
2024 and 2023	4,000	22,109
2023 and 2022	7,234	46,558
2022 and 2021	9,380	92,841
2021 and 2020	31,349	16,431
Prior	6,416	242
Revolving Loans	178,354	61,223
Total	255,335	257,169
Loans Receivable [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	9,143	4,494
Revolving Loans	0	0
Total	9,143	4,494
Loans Receivable [Member] \| Special Mention [Member] \| Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	8,502	2,588
Revolving Loans	0	0
Total	8,502	2,588
Loans Receivable [Member] \| Special Mention [Member] \| Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	641	1,906
Revolving Loans	0	0
Total	641	1,906
Loans Receivable [Member] \| Special Mention [Member] \| Construction Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	0	0
Revolving Loans	0	0
Total	0	0
Loans Receivable [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0
2024 and 2023	0
2023 and 2022	0
2022 and 2021	0
2021 and 2020	0
Prior	16,530
Revolving Loans	0
Total	16,530
Loans Receivable [Member] \| Substandard [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024		0
2024 and 2023		0
2023 and 2022		19
2022 and 2021		0
2021 and 2020		6,938
Prior		19,884
Revolving Loans		0
Total		26,841
Loans Receivable [Member] \| Substandard [Member] \| Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	6,938
Prior	15,313	18,503
Revolving Loans	0	0
Total	15,313	25,441
Loans Receivable [Member] \| Substandard [Member] \| Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	1,070	1,287
Revolving Loans	0	0
Total	1,070	1,287
Loans Receivable [Member] \| Substandard [Member] \| Construction Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025 and 2024	0	0
2024 and 2023	0	0
2023 and 2022	0	0
2022 and 2021	0	0
2021 and 2020	0	0
Prior	0	0
Revolving Loans	0	0
Total	$ 0	$ 0

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