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Income Tax Matters - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Income Tax Disclosure [Abstract] |  |  |  |  |
Income tax benefit (provision) | $ 15.5 | $ (1.3) | $ 15.8 | $ (10.9) |
Effective tax rate (percent) | 41.00% | (24.00%) | 47.00% | 33.00% |
Effective income tax rate reconciliation, increase (decrease) related to nondeductible expense, percent | 22.00% |  | 22.00% | 2.00% |
Effective income tax rate reconciliation, increase (decrease) related to permanent items not deductible for tax purposes | 4.00% |  | 4.00% |  |
Effective tax rate reconciliation, increase (decrease) related to foreign withholding tax | 5.00% |  | 5.00% |  |
Effective tax rate reconciliation, increase (decrease) to the valuation allowance for certain state net operating losses (percent) | 1.00% | 19.00% | 3.00% | 4.00% |
Effective income tax rate reconciliation, Federal R&D Credit | (15.00%) |  | (15.00%) |  |
Effective income tax rate reconciliation, change in forecasted earnings percent |  | 37.00% |  |  |
Effective income tax rate reconciliation, tax expense (benefit), share-based payment arrangement, percent | 1.00% |  | 2.00% | (2.00%) |
Effective tax rate reconciliation, foreign tax rate difference |  |  | 2.00% |  |
Effective income tax rate reconciliation, change in state tax rate, percent |  |  | 2.00% |  |
Gross unrecognized tax benefits | $ 4.0 |  | $ 4.0 |  | $ 3.8
Gross unrecognized tax benefits that would impact effective tax rate | $ 1.5 |  | $ 1.5 |  | $ 1.5

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