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Loans and Allowance for Credit Losses - Summary of Aging Analysis of Modifications (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	$ 22,918
Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	20,801
30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	1,610
60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	62
90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	445
Commercial Loans | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	13,505
Commercial Loans | Commercial real estate | Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	13,505
Commercial Loans | Commercial real estate | 30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial real estate | 60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial real estate | 90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	6,892
Commercial Loans | Commercial and industrial | Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	6,447
Commercial Loans | Commercial and industrial | 30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial and industrial | 60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial and industrial | 90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	445
Commercial Loans | Commercial construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	1,610
Commercial Loans | Commercial construction | Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial construction | 30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	1,610
Commercial Loans | Commercial construction | 60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Commercial Loans | Commercial construction | 90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Business banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	658
Business banking | Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	658
Business banking | 30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Business banking | 60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Business banking | 90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Consumer Loans | Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	253
Consumer Loans | Consumer real estate | Current | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	191
Consumer Loans | Consumer real estate | 30-59 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	0
Consumer Loans | Consumer real estate | 60-89 Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	62
Consumer Loans | Consumer real estate | 90+ Days Past Due | Accrual
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, after 12 months	$ 0

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