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Loans and Allowance for Credit Losses on Loans - Schedule of Allocation of the Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	$ 24,260	$ 23,832	$ 22,983	$ 22,963	$ 22,539	$ 23,023
Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	11,567		12,651
Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	12,686		10,323
Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	7		9
Commercial loans | Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1,808	1,831	1,794	1,958	1,699	1,709
Commercial loans | Commercial and industrial | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1,042		1,079
Commercial loans | Commercial and industrial | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	761		706
Commercial loans | Commercial and industrial | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	5		9
Commercial real estate loans | Commercial owner-occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	2,530	2,589	2,487	2,536	2,617	2,776
Commercial real estate loans | Commercial owner-occupied | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1,315		1,497
Commercial real estate loans | Commercial owner-occupied | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1,214		990
Commercial real estate loans | Commercial owner-occupied | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1		0
Commercial real estate loans | Commercial non-owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	13,624	13,201	12,676	12,738	12,439
Commercial real estate loans | Commercial non-owner occupied | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	7,324		7,937
Commercial real estate loans | Commercial non-owner occupied | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	6,300		4,739
Commercial real estate loans | Commercial non-owner occupied | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	0		0
Commercial real estate loans | Construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	2,018	1,942	1,937	1,784	1,737	1,653
Commercial real estate loans | Construction | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	213		453
Commercial real estate loans | Construction | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1,805		1,484
Commercial real estate loans | Construction | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	0		0
Residential loans | Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	565	561	558	542	530	595
Residential loans | Home equity | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	494		504
Residential loans | Home equity | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	71		54
Residential loans | Home equity | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	0		0
Residential loans | Other residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	605	599	595	590	585	644
Residential loans | Other residential | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	566		571
Residential loans | Other residential | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	38		24
Residential loans | Other residential | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	1		0
Consumer loans | Installment and other consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	951	940	868	815	733	621
Consumer loans | Installment and other consumer loans | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	613		610
Consumer loans | Installment and other consumer loans | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	338		258
Consumer loans | Installment and other consumer loans | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	0		0
Unallocated
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	2,159	$ 2,169	2,068	$ 2,000	$ 2,199	$ 2,286
Unallocated | Modeled expected credit losses
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	0		0
Unallocated | Qualitative adjustments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	2,159		2,068
Unallocated | Specific allocations
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit losses	$ 0		$ 0

X

- Definition

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

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