Annual report pursuant to Section 13 and 15(d)

Goodwill and Intangible Assets, Net of Accumulated Amortization (Components of Intangible Assets, at Cost) (Details)

v3.19.2
Goodwill and Intangible Assets, Net of Accumulated Amortization (Components of Intangible Assets, at Cost) (Details) - USD ($)
$ in Millions
May 31, 2019
May 31, 2018
Intangible Assets [Line Items]    
Total intangible assets, gross $ 631.2 $ 321.8
Less: Accumulated amortization 232.1 180.4
Intangible assets, net of accumulated amortization 399.1 141.4 [1]
Other Intangible Assets [Member]    
Intangible Assets [Line Items]    
Total intangible assets, gross 23.0 13.3
Client Lists [Member]    
Intangible Assets [Line Items]    
Total intangible assets, gross [2] $ 608.2 $ 308.5
[1] Amounts have been adjusted to reflect the adoption of ASC Topic 606 and to provide further detail related to certain professional employer organization ("PEO") balances.
[2] Client lists and other intangible assets include current estimates of amounts acquired from Oasis as of December 20, 2018. Refer to Note D of this Item 8 for further details.