Common Stock and Stock-Based Compensation - Stock Option Transactions Under Plan (Detail) - Stock Incentive Plan shares in Millions	12 Months Ended
	May 31, 2020 $ / shares shares
Options Outstanding - Shares
Beginning Balance (in shares) | shares	91.3
Exercised (in shares) | shares	(20.1)
Forfeited (in shares) | shares	(2.2)
Granted (in shares) | shares	19.1
Ending Balance (in shares) | shares	88.1
Options exercisable (in shares) | shares	48.5
Options Outstanding - Weighted-Average Option Price
Beginning Balance (in dollars per share) | $ / shares	$ 50.59
Exercised (in dollars per share) | $ / shares	35.26
Forfeited (in dollars per share) | $ / shares	75.74
Granted (in dollars per share) | $ / shares	85.29
Ending Balance (in dollars per share) | $ / shares	60.98
Options exercisable (in dollars per share) | $ / shares	$ 46.91