Annual report pursuant to Section 13 and 15(d)

Valuation and Qualifying Accounts (Details)

v3.10.0.1
Valuation and Qualifying Accounts (Details) - USD ($)
$ in Millions
 12 Months Ended
May 31, 2018
May 31, 2017
May 31, 2016
Allowance for Doubtful Accounts [Member]      
Valuation and Qualifying Accounts Disclosure [Line Items]      
Balance as of beginning of fiscal year $ 6.0 $ 4.2 $ 1.4
Additions charged to expenses 3.6 4.9 2.5
Additions to/(deductions from) other accounts [1] 2.0
Costs and deductions [2] 2.6 3.1 1.7
Balance as of end of fiscal year 7.0 6.0 4.2
Reserve for Client Fund Losses [Member]      
Valuation and Qualifying Accounts Disclosure [Line Items]      
Balance as of beginning of fiscal year 3.0 2.0 1.8
Additions charged to expenses 3.1 4.1 2.4
Additions to/(deductions from) other accounts [1]
Costs and deductions [2] 3.7 3.1 2.2
Balance as of end of fiscal year $ 2.4 $ 3.0 $ 2.0
[1] Amounts related to business acquisitions.
[2] Uncollectible amounts written off, net of recoveries.