Restructuring Charge - Narrative (Details) $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended
		Feb. 07, 2019 USD ($)	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($) employee	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($) employee
Restructuring and Related Activities [Abstract]
Restructuring charge	[1]	$ 0.1	$ 6.8	$ 17.4	$ 11.3	$ 35.9
Severance costs		$ 0.1	$ 4.2	$ 10.7	$ 6.2	$ 27.8
Number of employees impacted | employee			60	190	100	380
Contract termination, write-down of right-of-use assets and other exit costs			$ 2.6	$ 6.7	$ 5.1	$ 8.1

[1] See Note 1 "Basis of Presentation" for further discussion.