Leases - Lease Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Lease Cost
Amortization of Right-of-Use Assets - Finance Leases	$ 0.1	$ 0.2
Operating Lease Cost	5.6	5.7
Short-Term Lease Cost	0.0	0.1
Total Expense	5.7	6.0
Less: Sublease Income	0.0	(0.1)
Total Lease Cost	$ 5.7	$ 5.9