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Loans and Allowance for Credit Losses on Loans - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($)	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 24,260,000	$ 23,832,000	$ 22,983,000	$ 22,963,000	$ 22,539,000	$ 23,023,000
Nonaccrual collateral dependent loans in process of foreclosure	$ 0		$ 0
Weighted average ratio of loans value to collateral dependent loans value	61.00%		42.00%
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 5,672,000		$ 2,432,000
Allowance for credit losses	0		0
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	5,182,000		1,563,000
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	490,000		778,000
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		91,000
Commercial real estate loans | Commercial owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	2,530,000	2,589,000	2,487,000	2,536,000	2,617,000	2,776,000
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	4,281,000		1,563,000
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	4,281,000		1,563,000
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	13,624,000	13,201,000	12,676,000	12,738,000	12,439,000
Commercial real estate loans | Commercial non-owner occupied | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	901,000
Allowance for credit losses	0
Commercial real estate loans | Commercial non-owner occupied | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	901,000
Commercial real estate loans | Commercial non-owner occupied | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0
Commercial real estate loans | Commercial non-owner occupied | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0
Commercial real estate loans | Installment and other consumer loans | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			91,000
Allowance for credit losses			0
Commercial real estate loans | Installment and other consumer loans | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			0
Commercial real estate loans | Installment and other consumer loans | Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			0
Commercial real estate loans | Installment and other consumer loans | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans			91,000
Residential loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	565,000	561,000	558,000	542,000	530,000	595,000
Residential loans | Home equity | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	490,000		778,000
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	490,000		778,000
Residential loans | Home equity | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0		0
Residential loans | Other residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 605,000	$ 599,000	$ 595,000	$ 590,000	$ 585,000	$ 644,000

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-Publisher FASB
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