Unaudited Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Millions, $ in Millions	Total	CAPITAL IN EXCESS OF STATED VALUE	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	RETAINED EARNINGS (DEFICIT)	Class A Common Stock	Class A Common Stock COMMON STOCK	Class B Common Stock	Class B Common Stock COMMON STOCK
Beginning Balance (in shares) at May. 31, 2019						315		1,253
Beginning balance at May. 31, 2019	$ 9,040	$ 7,163	$ 231	$ 1,643		$ 0		$ 3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)								4
Stock options exercised	116	116
Repurchase of Class B Common Stock (in shares)								(12)
Repurchase of Class B Common Stock	(995)	(55)		(940)
Dividends on common stock and preferred stock	(344)			(344)
Issuance of shares to employees, net of shares withheld for employee taxes	(12)	(8)		(4)
Stock-based compensation	80	80
Net income	1,367			1,367
Other comprehensive income (loss)	(51)		(51)
Ending Balance (in shares) at Aug. 31, 2019						315		1,245
Ending balance at Aug. 31, 2019	9,200	7,296	180	1,721		$ 0		$ 3
Beginning Balance (in shares) at May. 31, 2020					315	315	1,243	1,243
Beginning balance at May. 31, 2020	8,055	8,299	(56)	(191)		$ 0		$ 3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)								7
Stock options exercised	291	291
Dividends on common stock and preferred stock	(383)			(383)
Issuance of shares to employees, net of shares withheld for employee taxes	(48)	(31)		(17)
Stock-based compensation	136	136
Net income	1,518			1,518
Other comprehensive income (loss)	(345)		(345)
Ending Balance (in shares) at Aug. 31, 2020					315	315	1,250	1,250
Ending balance at Aug. 31, 2020	$ 9,224	$ 8,695	$ (401)	$ 927		$ 0		$ 3