Summary of Significant Accounting Policies - Summary of Property and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 605.5	$ 613.6
Land
Property, Plant and Equipment [Line Items]
Property and equipment	0.5	3.4
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment	10.2	12.0
Furniture, Fixtures, and Autos
Property, Plant and Equipment [Line Items]
Property and equipment	164.8	167.3
Computer Equipment
Property, Plant and Equipment [Line Items]
Property and equipment	130.3	128.7
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 299.7	$ 302.2