Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Effective tax rates	20.00%	31.00%
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 30.7		$ 19.7
Reduction in provision for income taxes due to impact of effective tax rate	27.3
Deferred tax assets classified as other non-current assets	297.6		$ 227.2
Deferred tax assets, valuation allowance	23.5
Other Noncurrent Liabilities
Income Tax Contingency [Line Items]
Increase in unrecognized tax benefits is reasonably possible	12.8
Other Noncurrent Assets
Income Tax Contingency [Line Items]
Unrecognized tax benefits	17.9
Accounting Standards Update 2016-09
Income Tax Contingency [Line Items]
Increase to deferred tax assets	43.6
Effective income tax rate reconciliation, share-based compensation, excess tax benefit	36.0
Retained Earnings | Accounting Standards Update 2016-09
Income Tax Contingency [Line Items]
Cumulative effect adjustment to retained earnings	$ 43.6