Common Stock and Stock-Based Compensation - Total Stock-Based Compensation Expense (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense			$ 226	$ 158
Class B Common Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 93	$ 55	226	158
Class B Common Stock | Stock options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	62	38	145	110
Accelerated stock option expense	13	6	28	14
Class B Common Stock | ESPPs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	10	7	28	24
Class B Common Stock | Restricted stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 21	$ 10	$ 53	$ 24