Summary of Significant Accounting Policies - Schedule of Goodwill, Finite-Lived Intangible Assets and Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Millions		Dec. 31, 2022		Dec. 31, 2021		Dec. 31, 2020
Goodwill [Line Items]
Goodwill	[2]	$ 1,628.1	[1]	$ 1,722.2	[1]	$ 1,225.8
Finite-lived:
Gross		840.2		846.6
Accumulated Amortization		468.3		441.3
Net		371.9		405.3
Indefinite-lived:
Gross		177.6		178.3
Total intangible assets
Gross		1,017.8		1,024.9
Accumulated Amortization		468.3		441.3
Net		549.5		583.6
Tradenames
Indefinite-lived:
Gross	[3]	52.0		52.0
Reacquired franchise rights
Indefinite-lived:
Gross		125.6		126.3
Customer relationships
Finite-lived:
Gross		818.9		823.4
Accumulated Amortization		448.1		421.6
Net		370.8		401.8
Other
Finite-lived:
Gross		21.3		23.2
Accumulated Amortization		20.2		19.7
Net		$ 1.1		$ 3.5

[1] Balances were net of accumulated impairment loss of $694.2 and $644.2 as of December 31, 2022 and 2021, respectively.

[2] Balances were net of accumulated impairment loss of $644.2 ($127.0 related to Northern Europe, $3.8 related to APME, $235.2 related to Right Management and $278.2 related to corporate) as of both January 1, 2021 and December 31, 2021; and $694.2 ($177.0 related to Northern Europe, $3.8 related to APME, $235.2 related to Right Management and $278.2 related to Corporate) as of December 31, 2022.

[3] Balances were net of accumulated impairment loss of $139.5 as of both December 31, 2022 and 2021.