Quarterly report pursuant to Section 13 or 15(d)

Funds Held for Clients and Corporate Investments (Details 2)

v2.4.0.8
Funds Held for Clients and Corporate Investments (Details 2) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 9 Months Ended
Feb. 28, 2014
Security
Feb. 28, 2013
Feb. 28, 2014
Security
Feb. 28, 2013
May 31, 2013
Security
Maturity Date:          
Due in one year or less, Amortized cost $ 350.1   $ 350.1    
Due in one year or less, Fair value 352.6   352.6    
Due after one year through three years, Amortized cost 769.8   769.8    
Due after one year through three years, Fair value 788.5   788.5    
Due after three years through five years, Amortized cost 703.7   703.7    
Due after three years through five years, Fair value 716.3   716.3    
Due after five years, Amortized cost 1,226.7   1,226.7    
Due after five years, Fair value 1,232.1   1,232.1    
Total, Amortized cost 3,050.3   3,050.3    
Fair value 3,089.5   3,089.5   3,691.4
Funds Held for Clients and Corporate Investments (Textual)          
Net unrealized gain on available-for-sale securities 39.2   39.2   34.7
Number of available-for-sale securities in an unrealized loss position 85   85   147
Gross realized gains 0.3 0.6 0.5 0.9  
Gross realized losses $ 0 $ 0 $ 0 $ 0  
Minimum maturity period for VRDNs primarily categorized as due after five years (in years) 20 years   20 years    
Maximum maturity period for VRDNs, primarily categorized as due after five years (in years) 30 years   30 years