FAIR VALUE MEASUREMENTS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2013	May 31, 2013
Assets [Abstract]
Commercial paper debt securities	$ 15,978	$ 14,043
Corporate debt securities and other	7,920	4,935
Derivative financial instruments	35	41
Total assets	23,933	19,019
Liabilities [Abstract]
Derivative financial instruments	15
Total debt	24,100	18,500
Marketable security investments maturity information [Abstract]
Maturity of marketable security investments	As of August 31, 2013 and May 31, 2013, approximately 83% and 91%, respectively, of our marketable securities investments mature within one year and 17% and 9%, respectively, mature within one to four years.
Fair Value Measurements Using Input Types Level 1 [Member]
Assets [Abstract]
Corporate debt securities and other	149	246
Total assets	149	246
Fair Value Measurements Using Input Types Level 2 [Member]
Assets [Abstract]
Commercial paper debt securities	15,978	14,043
Corporate debt securities and other	7,771	4,689
Derivative financial instruments	35	41
Total assets	23,784	18,773
Liabilities [Abstract]
Derivative financial instruments	15
Total debt fair value	$ 25,500	$ 20,700