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Accounting Standards Updates Accounting Standards Updates - Additional Information (Details) - USD ($) $ in Thousands | Jan. 01, 2020 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of new accounting principle in period of adoption |  | $ (14,672) | $ (2,285)
Minimum [Member] | Scenario, Forecast [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Percentage increase in allowance for loan losses and reserve for unfunded commitments | 15.00% |  |
Maximum [Member] | Scenario, Forecast [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Percentage increase in allowance for loan losses and reserve for unfunded commitments | 25.00% |  |
Retained Earnings [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect of new accounting principle in period of adoption |  | $ (14,672) | $ (2,285)

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