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Loans and Allowance for Credit Losses on Loans - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($)	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 30,675,000	$ 30,675,000	$ 25,172,000	$ 24,260,000	$ 23,832,000	$ 22,983,000
Nonaccrual collateral dependent loans in process of foreclosure	$ 0		$ 0
Weighted average ratio of loans value to collateral dependent loans value	120.00%		70.00%
Weighted average ratio of loans value to collateral dependent loans value, net of credit loss reserves	84.00%		62.00%
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 32,400,000		$ 5,295,000
Allowance for credit losses	7,971,000		408,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	30,807,000		4,826,000
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,161,000		469,000
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	432,000		0
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	1,718,000	1,876,000	1,712,000	1,808,000	1,831,000	1,794,000
Commercial loans | Commercial and industrial | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			1,311,000
Allowance for credit losses			0
Commercial loans | Commercial and industrial | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			1,311,000
Commercial loans | Commercial and industrial | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			0
Commercial loans | Commercial and industrial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			0
Commercial real estate loans | Commercial owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	2,345,000	2,408,000	2,476,000	2,530,000	2,589,000	2,487,000
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,578,000		434,000
Allowance for credit losses	0		0
Commercial real estate loans | Commercial owner-occupied | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,578,000		434,000
Commercial real estate loans | Commercial owner-occupied | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Commercial real estate loans | Commercial owner-occupied | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Commercial real estate loans | Commercial non-owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	22,100,000	22,165,000	14,933,000	13,624,000	13,201,000	12,676,000
Commercial real estate loans | Commercial non-owner occupied | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	29,229,000		3,081,000
Allowance for credit losses	7,971,000		408,000
Commercial real estate loans | Commercial non-owner occupied | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	29,229,000		3,081,000
Commercial real estate loans | Commercial non-owner occupied | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Commercial real estate loans | Commercial non-owner occupied | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Residential loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	647,000	650,000	552,000	565,000	561,000	558,000
Residential loans | Home equity | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,161,000		469,000
Allowance for credit losses	0		0
Residential loans | Home equity | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Residential loans | Home equity | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,161,000		469,000
Residential loans | Home equity | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Consumer loans | Installment and other consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	920,000	$ 910,000	$ 976,000	$ 951,000	$ 940,000	$ 868,000
Consumer loans | Installment and other consumer loans | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	432,000
Allowance for credit losses	0
Consumer loans | Installment and other consumer loans | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0
Consumer loans | Installment and other consumer loans | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0
Consumer loans | Installment and other consumer loans | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 432,000

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