Leases - Amounts Recognized for Leases (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Leases, Operating [Abstract]
Operating lease right-of-use assets	$ 103.0	$ 96.8
Current operating lease liabilities	$ 32.1	$ 29.6
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent
Other non-current liabilities	$ 74.9	$ 71.7
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent	us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent
TOTAL LIABILITIES	$ 107.0	$ 101.3