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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Operating Loss Carryforwards [Line Items] |  |  |  |
Effective income tax rate | 53.50% | (31.70%) | 10.80% | 5.40%
Income Tax Benefit Offset Amount From Cares Act 2020 Aid | $ 106.0 |  | $ 206.0 |
Net operating losses carried back term due to cares act |  |  | 5 years |
Favorably impacted by an income tax benefit | 90.3 |  | $ 90.3 |
Income tax receivable recorded in current assets | 112.0 |  | 112.0 |
Income tax receivable recorded in other assets | $ 90.3 |  | $ 90.3 |

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