Loans and Allowance for Credit Losses - Loans Outstanding and Aging Analysis (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	$ 2,092,546,000	$ 2,255,645,000
Non-accrual loans	2,432,000	8,376,000
Non-accrual loans with no allowance	$ 2,432,000	$ 8,376,000
Number of loans past due more than 90 days still accruing \| loan	0	0
Nonaccrual loans earning interest on cash basis	$ 0	$ 0
Nonaccrual interest income	0	0	$ 0
Accrued interest writeoff	48,000	0
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	2,092,546,000	2,255,645,000
Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	1,342,000	2,314,000
30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	420,000	1,536,000
60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	244,000	461,000
90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	678,000	317,000
Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	2,091,204,000	2,253,331,000
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	173,547,000	301,602,000
Non-accrual loans	0	0
Non-accrual loans with no allowance	0	0
Commercial \| Commercial and industrial \| Small Business Administration Paycheck Protection Program
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	3,500,000	111,200,000	$ 444,100,000
Commercial \| Commercial and industrial \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	173,547,000	301,602,000
Commercial \| Commercial and industrial \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	267,000	625,000
Commercial \| Commercial and industrial \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	3,000	2,000
Commercial \| Commercial and industrial \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	394,000
Commercial \| Commercial and industrial \| 90 days or more past due 1 \| Small Business Administration Paycheck Protection Program
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	264,000	229,000
Commercial \| Commercial and industrial \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	264,000	229,000
Commercial \| Commercial and industrial \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	173,280,000	300,977,000
Commercial real estate \| Commercial owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	354,877,000	392,345,000
Non-accrual loans	1,563,000	7,269,000
Non-accrual loans with no allowance	1,563,000	7,269,000
Commercial real estate \| Commercial owner-occupied \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	354,877,000	392,345,000
Commercial real estate \| Commercial owner-occupied \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial owner-occupied \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial owner-occupied \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial owner-occupied \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial owner-occupied \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	354,877,000	392,345,000
Commercial real estate \| Commercial investor-owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	1,191,889,000	1,189,021,000
Non-accrual loans	0	694,000
Non-accrual loans with no allowance	0	694,000
Commercial real estate \| Commercial investor-owned \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	1,191,889,000	1,189,021,000
Commercial real estate \| Commercial investor-owned \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial investor-owned \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial investor-owned \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial investor-owned \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Commercial investor-owned \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	1,191,889,000	1,189,021,000
Commercial real estate \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	114,373,000	119,840,000
Non-accrual loans	0	0
Non-accrual loans with no allowance	0	0
Commercial real estate \| Construction \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	114,373,000	119,840,000
Commercial real estate \| Construction \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Construction \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Construction \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Construction \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Commercial real estate \| Construction \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	114,373,000	119,840,000
Residential loans \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	88,748,000	88,746,000
Non-accrual loans	778,000	413,000
Non-accrual loans with no allowance	778,000	413,000
Residential loans \| Home equity \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	88,748,000	88,746,000
Residential loans \| Home equity \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	977,000	653,000
Residential loans \| Home equity \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	319,000	498,000
Residential loans \| Home equity \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	244,000	67,000
Residential loans \| Home equity \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	414,000	88,000
Residential loans \| Home equity \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	87,771,000	88,093,000
Residential loans \| Other residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	112,123,000	114,558,000
Non-accrual loans	0	0
Non-accrual loans with no allowance	0	0
Residential loans \| Other residential \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	112,123,000	114,558,000
Residential loans \| Other residential \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	93,000	0
Residential loans \| Other residential \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	93,000	0
Residential loans \| Other residential \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Residential loans \| Other residential \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Residential loans \| Other residential \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	112,030,000	114,558,000
Consumer loans \| Installment and other consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	56,989,000	49,533,000
Non-accrual loans	91,000	0
Non-accrual loans with no allowance	91,000	0
Consumer loans \| Installment and other consumer loans \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	56,989,000	49,533,000
Consumer loans \| Installment and other consumer loans \| Total past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	5,000	1,036,000
Consumer loans \| Installment and other consumer loans \| 30-59 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	5,000	1,036,000
Consumer loans \| Installment and other consumer loans \| 60-89 days past due \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Consumer loans \| Installment and other consumer loans \| 90 days or more past due 1 \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	0	0
Consumer loans \| Installment and other consumer loans \| Current \| Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	$ 56,984,000	$ 48,497,000