Income Taxes (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	Jun. 10, 2014
Valuation Allowance [Line Items]
Effective income tax rate	16.60%	28.30%	12.30%	32.20%
Income before income taxes, domestic operations			$ 29.2	$ 32.2
Income before income taxes, foreign operations			107.1	120.2
Liabilities for uncertain income tax positions	$ 54.2		54.2		$ 57.1
Cash paid for income taxes			51.8	$ 33.5
Prepaid tax payments	12.6		12.6		$ 3.0
Decrease in deferred tax liability	44.2		44.2
Increase in additional paid-in capital	$ 44.2		$ 44.2
3.25% Convertible Notes | Convertible Debt
Valuation Allowance [Line Items]
Stated interest rate						3.25%