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Summary of Significant Accounting Policies - Narrative (Details) |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Nov. 30, 2020 USD ($) | Nov. 30, 2019 USD ($) | Dec. 31, 2021 USD ($) subsidiary entity reporting_unit | Dec. 31, 2020 USD ($)
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Number of wholly owned subsidiaries | subsidiary |  |  | 5 |
Percentage of outstanding common stock of investees accounted for using equity method of accounting |  |  | 100.00% |
Number of entities non-banking activities | entity |  |  | 6 |
Goodwill |  |  | $ 373,424,000 | $ 373,424,000
Prior period reclassification adjustment |  |  | $ 0 |
Period for satisfactory payment of TDRs |  |  | 6 months |
Threshold for evaluation for expected credit loss of commercial loans |  |  | $ 1,000,000 |
Number of reporting units | reporting_unit |  |  | 1 |
Number of wholly owned trust subsidiaries | subsidiary |  |  | 3 |
Minimum | Core Deposits And Customers Lists |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Weighted average estimated useful of acquired intangibles |  |  | 10 years |
Maximum |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Amortization period of investments in joint ventures |  |  | 10 years |
Maximum | Core Deposits And Customers Lists |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Weighted average estimated useful of acquired intangibles |  |  | 20 years |
Corporate Joint Venture | Common Wealth Trust Life Insurance Company |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of outstanding common stock of investees accounted for using equity method of accounting |  |  | 50.00% |
Interest rate lock commitments |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Period for interest rate lock commitment |  |  | 60 days |
DNB |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Fair value of consideration | $ 200,991,000 | $ 200,991,000 |  |
Total assets acquired |  | 1,100,000,000 |  |
Loans acquired |  | 909,000,000 |  |
Goodwill | 85,978,000 | 84,175,000 |  | $ 86,000,000
Deposits acquired | $ 967,265,000 | $ 967,265,000 |  |

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