DERIVATIVE FINANCIAL INSTRUMENTS Narrative (Details) - USD ($) $ in Billions	3 Months Ended
	Aug. 31, 2018	May 31, 2018
Foreign Currency Forward Contracts Not Designated as Hedges [Abstract]
Description of foreign currency forward contracts not designated as hedges	We also held certain foreign currency contracts that were not designated as hedges pursuant to ASC 815. As of August 31, 2018 and May 31, 2018, the notional amounts of such forward contracts we held to purchase U.S. Dollars in exchange for other major international currencies were $2.9 billion and $3.4 billion, respectively, and the notional amount of forward contracts we held to sell U.S. Dollars in exchange for other major international currencies were $1.5 billion and $1.4 billion, respectively. The fair values of our outstanding foreign currency forward contracts were nominal as of August 31, 2018 and May 31, 2018.
Forward contracts held to purchase U.S. Dollars [Member] | Foreign Currency Forward Contracts Not Designated as Hedges [Member]
Foreign Currency Forward Contracts Not Designated as Hedges (Narrative) [Abstract]
Notional amounts of forward contracts	$ 2.9	$ 3.4
Forward contracts held to sell U.S. Dollars [Member] | Foreign Currency Forward Contracts Not Designated as Hedges [Member]
Foreign Currency Forward Contracts Not Designated as Hedges (Narrative) [Abstract]
Notional amounts of forward contracts	$ 1.5	$ 1.4