Annual report pursuant to Section 13 and 15(d)

Funds Held for Clients and Corporate Investments (Funds Held for Clients and Corporate Investments) (Details)

v3.22.2
Funds Held for Clients and Corporate Investments (Funds Held for Clients and Corporate Investments) (Details) - USD ($)
$ in Millions
May 31, 2022
May 31, 2021
Schedule of Available-for-sale Securities [Line Items]    
Funds held for clients' money market securities and other restricted cash equivalents, Amortized cost $ 482.6 $ 739.6
Funds held for clients' money market securities and other restricted cash equivalents, Fair value 482.6 739.6
AFS securities, Amortized cost 4,165.5 2,940.9
AFS securities, Gross unrealized gains 2.7 83.3
AFS securities, Gross unrealized losses (139.0) (4.0)
AFS securities, Fair value 4,029.2 3,020.2
Other, Amortized cost 30.4 26.4
Other, Gross unrealized gains 1.8 7.7
Other, Gross unrealized losses (2.2) (0.1)
Other, Fair value 30.0 34.0
Total funds held for clients and corporate investments, Amortized cost 4,678.5 3,706.9
Total funds held for clients and corporate investments, Gross unrealized gains 4.5 91.0
Total funds held for clients and corporate investments, Gross unrealized losses (141.2) (4.1)
Total funds held for clients and corporate investments, Fair value 4,541.8 3,793.8
Asset-Backed Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
AFS securities, Amortized cost 68.5 86.5
AFS securities, Gross unrealized gains 0.0 1.4
AFS securities, Gross unrealized losses (1.3)  
AFS securities, Fair value 67.2 87.9
Corporate Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
AFS securities, Amortized cost 699.3 635.8
AFS securities, Gross unrealized gains 1.8 28.8
AFS securities, Gross unrealized losses (19.0) (0.2)
AFS securities, Fair value 682.1 664.4
Municipal Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
AFS securities, Amortized cost 1,577.6 1,669.0
AFS securities, Gross unrealized gains 0.6 33.0
AFS securities, Gross unrealized losses (92.4) (2.3)
AFS securities, Fair value 1,485.8 1,699.7
U.S. Government Agency And Treasury Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
AFS securities, Amortized cost 574.5 549.6
AFS securities, Gross unrealized gains 0.3 20.1
AFS securities, Gross unrealized losses (26.3) (1.5)
AFS securities, Fair value 548.5 $ 568.2
Variable Rate Demand Notes [Member]    
Schedule of Available-for-sale Securities [Line Items]    
AFS securities, Amortized cost 1,245.6  
AFS securities, Fair value $ 1,245.6