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Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2019 | Sep. 30, 2017
Income Tax Disclosures [Line Items] |  |  |
Statutory tax rate |  |  | 35.00%
Tax benefit from re-measurement of deferred tax assets and liabilities | $ 3,700 |  |
Scenario, Forecast |  |  |
Income Tax Disclosures [Line Items] |  |  |
Statutory tax rate |  | 21.00% |

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