Leases - Lease Cost (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019 USD ($)
Lease Cost
Amortization of Right-of-Use Assets	$ 0.5
Operating Lease Cost	15.5
Short-Term Lease Cost	0.1
Total Expense	16.1
Less: Sublease Income	(0.1)
Total Lease Cost	$ 16.0