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Loans Receivable and Allowance for Credit Losses - Individually Evaluated for Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	$ 7,187	$ 7,795	$ 7,305	$ 14,984	$ 14,989	$ 15,925
Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	1,680		463
Collectively evaluated loans	5,507		6,842
Total allowance for credit losses	7,187		7,305
Individually evaluated loans	24,726		25,015
Collectively evaluated loans	563,940		682,457
Loans receivable, gross	588,666		707,472
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	2,504	2,436	2,241	9,045	7,958	6,089
Commercial Real Estate \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	116		403
Collectively evaluated loans	2,388		1,838
Total allowance for credit losses	2,504		2,241
Individually evaluated loans	20,109		19,335
Collectively evaluated loans	340,693		400,154
Loans receivable, gross	360,802		419,489
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	805	519	596	608	678	607
Residential Real Estate \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	0		0
Collectively evaluated loans	805		596
Total allowance for credit losses	805		596
Individually evaluated loans	57		0
Collectively evaluated loans	83,615		92,215
Loans receivable, gross	83,672		92,215
Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	3,430	1,785	1,077	1,056	1,215	1,269
Commercial and Industrial \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	1,564		60
Collectively evaluated loans	1,866		1,017
Total allowance for credit losses	3,430		1,077
Individually evaluated loans	4,529		3,323
Collectively evaluated loans	118,830		126,285
Loans receivable, gross	123,359		129,608
Consumer and Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	448	3,050	3,386	4,273	5,133	7,843
Consumer and Other \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	0		0
Collectively evaluated loans	448		3,386
Total allowance for credit losses	448		3,386
Individually evaluated loans	0		0
Collectively evaluated loans	20,802		59,973
Loans receivable, gross	20,802		59,973
Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	0	5	5	2	5	4
Construction \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	0		0
Collectively evaluated loans	0		5
Total allowance for credit losses	0		5
Individually evaluated loans	0		0
Collectively evaluated loans	0		3,830
Loans receivable, gross	0		3,830
Construction to Permanent - CRE
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance for credit losses	0	$ 0	0	$ 0	$ 0	$ 113
Construction to Permanent - CRE \| Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated loans	0		0
Collectively evaluated loans	0		0
Total allowance for credit losses	0		0
Individually evaluated loans	31		2,357
Collectively evaluated loans	0		0
Loans receivable, gross	$ 31		$ 2,357