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Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jan. 01, 2020 USD ($) | Dec. 31, 2021 USD ($) segment | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Basis Of Presentation [Line Items] |  |  |  |  |  |
Federal funds sold |  | $ 65,100 | $ 158,700 |  |  |
Total shareholders’ equity |  | $ 5,296,800 | 5,161,334 | $ 4,941,690 |  | $ 3,133,602
Number of reportable segments | segment |  | 3 |  |  |  |
Federal reserve bank stock |  | $ 143,700 | 142,500 |  |  |
Required percent of capital or surplus |  | 6.00% |  |  |  |
Required percent of deposits |  | 0.60% |  |  |  |
Federal home loan bank stock |  | $ 16,200 | 15,000 |  |  |
Vesting period |  | 3 years |  |  |  |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Total shareholders’ equity |  |  |  | (35,721) | [1] | 4,270
Retained Earnings |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Total shareholders’ equity |  | $ 1,709,980 | $ 1,178,019 | 1,068,327 |  | 843,767
Retained Earnings | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Total shareholders’ equity | $ 35,700 |  |  | $ (35,721) | [1] | $ 4,270
Non-employee Director |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Vesting period |  | 3 years |  |  |  |
Non-employee |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Vesting period |  | 3 years |  |  |  |
Unfunded Loan Commitment |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Financing receivable, purchased with credit deterioration, amount at purchase price | $ 62,200 |  |  |  |  |
DRR Methodology |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Loans, net |  | 41.00% | 40.00% |  |  |
Minimum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 8 years |  |  |  |
Minimum | Buildings and improvements |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 10 years |  |  |  |
Minimum | Furniture, equipment and software |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 3 years |  |  |  |
Minimum | Software and Software Development Costs |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 3 years |  |  |  |
Maximum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 10 years |  |  |  |
Maximum | Buildings and improvements |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 40 years |  |  |  |
Maximum | Furniture, equipment and software |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 10 years |  |  |  |
Maximum | Software and Software Development Costs |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 7 years |  |  |  |
[1] | For additional information, see "Part II - Item 8. Financial Statements and Supplementary Data - Note 1 - Summary of Significant Accounting Policies.

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