Common Stock and Stock-Based Compensation - Stock Option Transactions Under Plan (Detail) - Stock Incentive Plan shares in Millions	12 Months Ended
	May 31, 2019 $ / shares shares
Options Outstanding - Shares
Beginning Balance (in shares) | shares	93.2
Exercised (in shares) | shares	(18.2)
Forfeited (in shares) | shares	(1.8)
Granted (in shares) | shares	18.1
Ending Balance (in shares) | shares	91.3
Options exercisable (in shares) | shares	54.4
Options Outstanding - Weighted-Average Option Price
Beginning Balance (in dollars per share) | $ / shares	$ 40.73
Exercised (in dollars per share) | $ / shares	29.70
Forfeited (in dollars per share) | $ / shares	66.66
Granted (in dollars per share) | $ / shares	81.79
Ending Balance (in dollars per share) | $ / shares	50.59
Options exercisable (in dollars per share) | $ / shares	$ 37.82