Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Aug. 31, 2018	May 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash	$ 436	$ 415
Assets at Fair Value	4,280	5,256
Cash and Equivalents	3,282	4,249
Short-term Investments	987	996
Other Long-term Assets	11	11
Fair Value Measurements Using Level 1 | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	851	1,178
Cash and Equivalents	50	500
Short-term Investments	801	678
Other Long-term Assets	0	0
Fair Value Measurements Using Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	2,982	3,652
Cash and Equivalents	2,796	3,334
Short-term Investments	186	318
Other Long-term Assets	0	0
Fair Value Measurements Using Level 2 | Time deposits
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	1,098	925
Cash and Equivalents	1,081	907
Short-term Investments	17	18
Other Long-term Assets	0	0
Fair Value Measurements Using Level 2 | U.S. Agency securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	1	102
Cash and Equivalents	0	100
Short-term Investments	1	2
Other Long-term Assets	0	0
Fair Value Measurements Using Level 2 | Commercial paper and bonds
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	194	451
Cash and Equivalents	26	153
Short-term Investments	168	298
Other Long-term Assets	0	0
Fair Value Measurements Using Level 2 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	1,689	2,174
Cash and Equivalents	1,689	2,174
Short-term Investments	0	0
Other Long-term Assets	0	0
Fair Value Measurements Using Level 3 | Non-marketable preferred stock
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Assets at Fair Value	11	11
Cash and Equivalents	0	0
Short-term Investments	0	0
Other Long-term Assets	$ 11	$ 11