Loans Receivable and the Allowance for Credit Losses - Summary of risk category of loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Loans Receivable and the Allowance for Loan Losses
2023	$ 466,030
2022	581,524
2021	243,682
2020	73,291
2019	27,163
Prior	100,664
Revolving Loans Amortized Cost Basis	91,312
Revolving Loans Converted to Term	3,055
Total	1,586,721	$ 1,217,321
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff
2023	154
Prior	159
Total	313
Residential Real Estate
Loans Receivable and the Allowance for Loan Losses
2023	81,379
2022	71,932
2021	24,504
2020	11,611
2019	1,326
Prior	43,070
Total	233,822	150,754
Non-residential Real Estate
Loans Receivable and the Allowance for Loan Losses
2023	1,602
2022	251
2021	1,841
2020	995
2019	379
Prior	16,062
Total	21,130	25,324
Construction
Loans Receivable and the Allowance for Loan Losses
2023	376,763
2022	501,012
2021	216,901
2020	60,250
2019	25,150
Prior	39,337
Total	1,219,413	930,628
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff
Prior	159
Total	159
Commercial and Industrial
Loans Receivable and the Allowance for Loan Losses
2023	5,057
2022	8,329
2021	436
2020	435
2019	308
Prior	2,195
Revolving Loans Amortized Cost Basis	91,301
Revolving Loans Converted to Term	3,055
Total	111,116	110,069
Consumer
Loans Receivable and the Allowance for Loan Losses
2023	1,229
Revolving Loans Amortized Cost Basis	11
Total	1,240	546
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff
2023	154
Total	154
Pass
Loans Receivable and the Allowance for Loan Losses
2023	466,030
2022	581,524
2021	243,682
2020	67,991
2019	27,163
Prior	100,664
Revolving Loans Amortized Cost Basis	91,312
Revolving Loans Converted to Term	3,055
Total	1,581,421	1,215,520
Pass \| Residential Real Estate
Loans Receivable and the Allowance for Loan Losses
2023	81,379
2022	71,932
2021	24,504
2020	10,696
2019	1,326
Prior	43,070
Total	232,907	148,953
Pass \| Non-residential Real Estate
Loans Receivable and the Allowance for Loan Losses
2023	1,602
2022	251
2021	1,841
2020	995
2019	379
Prior	16,062
Total	21,130	25,324
Pass \| Construction
Loans Receivable and the Allowance for Loan Losses
2023	376,763
2022	501,012
2021	216,901
2020	55,865
2019	25,150
Prior	39,337
Total	1,215,028	930,628
Pass \| Commercial and Industrial
Loans Receivable and the Allowance for Loan Losses
2023	5,057
2022	8,329
2021	436
2020	435
2019	308
Prior	2,195
Revolving Loans Amortized Cost Basis	91,301
Revolving Loans Converted to Term	3,055
Total	111,116	110,069
Pass \| Consumer
Loans Receivable and the Allowance for Loan Losses
2023	1,229
Revolving Loans Amortized Cost Basis	11
Total	1,240	546
Special Mention
Loans Receivable and the Allowance for Loan Losses
2020	915
Total	915	946
Special Mention \| Residential Real Estate
Loans Receivable and the Allowance for Loan Losses
2020	915
Total	915	946
Substandard
Loans Receivable and the Allowance for Loan Losses
2020	4,385
Total	4,385	855
Substandard \| Residential Real Estate
Loans Receivable and the Allowance for Loan Losses
Total		$ 855
Substandard \| Construction
Loans Receivable and the Allowance for Loan Losses
2020	4,385
Total	$ 4,385

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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