Properties and Equipment Properties and Equipment- Lease Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases- Lease Cost [Abstract]
Operating Lease, Cost	$ 12.1
Short-term and variable lease cost	17.9
Lease, Cost	30.0
Operating Lease, Payments	12.0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 17.0
Operating Leases, Rent Expense, Net		$ 13.5	$ 11.3
Operating Lease, Weighted Average Discount Rate, Percent	6.40%
Operating Lease, Weighted Average Remaining Lease Term	8 years 2 months 12 days