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Summary of Significant Accounting Policies - Narrative (Details) | 12 Months Ended |  |
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Dec. 31, 2024 USD ($) entity subsidiary reporting_unit | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Summary of Significant Accounting Policies [Line Items] |  |  |
Number of wholly owned subsidiaries | subsidiary | 4 |  |
Number of entities non-banking activities | entity | 6 |  |
Prior period reclassification adjustment | $ 0 |  |
Threshold for evaluation for expected credit loss of commercial loans | $ 1,000,000.0 |  |
Finance Lease, Liability, Statement of Financial Position [Extensible List] | Premises and equipment, net | Premises and equipment, net |
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
Number of reporting units | reporting_unit | 1 |  |
Number of wholly owned trust subsidiaries | subsidiary | 2 |  |
Adjustment to allowance for credit loss | $ 101,494,000 | $ 107,966,000 | $ 101,340,000
Retained earnings | $ 1,039,035,000 | $ 959,604,000 |
Cumulative Effect, Period of Adoption, Adjustment |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |
Adjustment to allowance for credit loss |  |  | $ 568,000
Minimum | Core Deposits And Customers Lists |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |
Weighted average estimated useful of acquired intangibles | 10 years |  |
Maximum | Core Deposits And Customers Lists |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |
Weighted average estimated useful of acquired intangibles | 20 years |  |
Common Wealth Trust Life Insurance Company | CTCLIC |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |
Percentage of equity owned | 50.00% |  |
Interest rate lock commitments - mortgage loans |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |
Period for interest rate lock commitment | 60 days |  |

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