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

Effective income tax rate reconciliation permanent items nondeductible for tax purpose.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the income tax rates.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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