Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies (Amount Available) (Details)

v3.5.0.2
Commitments and Contingencies (Amount Available) (Details) - Line of Credit [Member]
$ in Millions
 12 Months Ended
May 31, 2016
USD ($)
JP Morgan Chase Bank, N.A. [Member]  
Line of Credit Facility [Line Items]  
Amount available $ 350
Expiration date Feb. 27, 2017
Bank of America, N.A. [Member]  
Line of Credit Facility [Line Items]  
Amount available $ 250
Expiration date Feb. 28, 2017
PNC Bank, National Association [Member]  
Line of Credit Facility [Line Items]  
Amount available $ 150
Expiration date Feb. 27, 2017
Wells Fargo Bank, National Association [Member]  
Line of Credit Facility [Line Items]  
Amount available $ 150
Expiration date Feb. 27, 2017