Leases - Amortization, Capital Lease Obligation and Rent Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Amortization expense	$ 24.1	$ 22.7
Rent expense:
Minimum rent payments	69.8	66.5
Contingent and other rents	24.9	24.1
Other	9.1	8.9
Total rent expense	$ 103.8	$ 99.5