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Income Tax Matters - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Income Tax Disclosure [Abstract] |  |  |  |  |
Income tax (provision) benefit | $ (8.4) | $ 0.7 | $ 7.4 | $ (10.2) |
Effective tax rate (percent) | 137.00% | 222.00% | 27.00% | 31.00% |
Effective income tax rate reconciliation, change in forecasted earnings percent | 116.00% | (211.00%) |  |  |
Effective tax rate reconciliation, increase (decrease) to the valuation allowance for certain state net operating losses (percent) | (2.00%) | 22.00% | 4.00% | 4.00% |
Effective income tax rate reconciliation, tax expense (benefit), share-based payment arrangement, percent | (1.00%) |  | 2.00% | (2.00%) |
Effective income tax rate reconciliation, tax credits, percent |  |  | 3.00% |  |
Effective income tax rate reconciliation, change in state tax rate, percent |  |  | 2.00% |  |
Effective income tax rate reconciliation, decrease to permanent items including nondeductible compensation expense and foreign withholding tax |  |  | (7.00%) |  |
Effective income tax rate reconciliation, nondeductible expense, percent |  |  |  | 4.00% |
Gross unrecognized tax benefits | $ 4.1 |  | $ 4.1 |  | $ 3.8
Gross unrecognized tax benefits that would impact effective tax rate | $ 4.1 |  | $ 4.1 |  | $ 3.8

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