Segment Data - Schedule of Segment Data (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Revenues from services	$ 3,742.2	$ 5,373.1	$ 8,361.3	$ 10,418.0
Franchise revenue	128.1	163.2	210.4	406.2
Franchise fees
Segment Reporting Information [Line Items]
Revenues from services	2.8	4.1	6.1	9.7
Americas
Segment Reporting Information [Line Items]
Revenues from services	836.6	1,068.2	1,847.6	2,098.4
Americas | United States
Segment Reporting Information [Line Items]
Revenues from services	515.9	652.7	1,126.8	1,275.9
Americas | United States | Franchise fees
Segment Reporting Information [Line Items]
Revenues from services	2.4	3.7	5.4	7.3
Franchise revenue	$ 122.3	$ 154.3	$ 198.8	$ 311.2