Annual report pursuant to Section 13 and 15(d)

Short-term Financing (Credit Facility Amount Borrowed) (Details)

v3.19.2
Short-term Financing (Credit Facility Amount Borrowed) (Details) - Revolving Credit Facility [Member] - USD ($)
$ in Millions
12 Months Ended
May 31, 2019
May 31, 2018
JPM $1 Billion Credit Facility [Member] | JP Morgan Chase Bank, N.A. [Member]    
Line of Credit Facility [Line Items]    
Number of days borrowed 95 days 22 days
Maximum amount borrowed $ 483.0 $ 700.0
Weighted-average amount borrowed $ 387.7 $ 319.1
Weighted-average interest rate 3.64% 4.27%
JPM $500 Million Credit Facility [Member] | JP Morgan Chase Bank, N.A. [Member]    
Line of Credit Facility [Line Items]    
Number of days borrowed 92 days 42 days
Maximum amount borrowed $ 400.0 $ 400.0
Weighted-average amount borrowed $ 375.6 $ 144.8
Weighted-average interest rate 3.55% 2.80%
PNC $150 Million Credit Facility [Member] | PNC Bank, National Association [Member]    
Line of Credit Facility [Line Items]    
Number of days borrowed 359 days 358 days
Maximum amount borrowed $ 58.9 $ 59.9
Weighted-average amount borrowed $ 56.1 $ 57.2
Weighted-average interest rate 2.81% 1.94%