Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	May 31, 2020	May 31, 2019
Assets, Fair Value Disclosure [Abstract]
Cash	$ 596	$ 853
ASSETS AT FAIR VALUE	8,787	4,663
CASH AND EQUIVALENTS	8,348	4,466
SHORT-TERM INVESTMENTS	439	197
Fair Value, Inputs, Level 1 | U.S. Treasury securities
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	1,204	347
CASH AND EQUIVALENTS	800	200
SHORT-TERM INVESTMENTS	404	147
Fair Value, Inputs, Level 2
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	6,987	3,463
CASH AND EQUIVALENTS	6,952	3,413
SHORT-TERM INVESTMENTS	35	50
Fair Value, Inputs, Level 2 | Commercial paper and bonds
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	32	34
CASH AND EQUIVALENTS	0	1
SHORT-TERM INVESTMENTS	32	33
Fair Value, Inputs, Level 2 | Money market funds
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	5,973	1,637
CASH AND EQUIVALENTS	5,973	1,637
SHORT-TERM INVESTMENTS	0	0
Fair Value, Inputs, Level 2 | Time deposits
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	981	1,791
CASH AND EQUIVALENTS	979	1,775
SHORT-TERM INVESTMENTS	2	16
Fair Value, Inputs, Level 2 | U.S. Agency securities
Assets, Fair Value Disclosure [Abstract]
ASSETS AT FAIR VALUE	1	1
CASH AND EQUIVALENTS	0	0
SHORT-TERM INVESTMENTS	$ 1	$ 1