Quarterly report pursuant to Section 13 or 15(d)

Borrowings (Details Textual 1)

v3.5.0.1
Borrowings (Details Textual 1) - USD ($)
May 31, 2016
Apr. 30, 2012
Feb. 29, 2016
Debt Instrument [Line Items]      
Derivative fixed average interest rate 1.10% 2.80%  
Interest rate swap contracts [Member] | Designated as hedging instrument [Member]      
Debt Instrument [Line Items]      
Notional value of interest rate swap agreements $ 700,000,000   $ 600,000,000
Interest rate swap contracts [Member] | Designated as hedging instrument [Member] | Cash flow hedging [Member]      
Debt Instrument [Line Items]      
Notional value of interest rate swap agreements 200,000,000    
LIBOR [Member]      
Debt Instrument [Line Items]      
Floating LIBOR rate debt $ 200,000,000 $ 500,000,000