INCOME TAXES - Reconciliation of Differences Between Federal Statutory Tax Rate and Effective Tax Rate (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2018	Dec. 31, 2017	May 31, 2019	May 31, 2018	May 31, 2017
Reconciliation of Differences Between Amount Computed by Applying Federal Statutory Rate to our Income Before Provision for Income Taxes and Provision for Income Taxes [Abstract]
Federal statutory income tax rate, percent	21.00%	35.00%	21.00%	29.20%	35.00%
Tax provision at statutory rate			$ 2,576	$ 3,629	$ 4,088
Impact of Tax Cuts and Jobs Act of 2017
One-time transition tax			(529)	7,781	0
Deferred tax effects			140	(911)	0
Foreign earnings at other than United States rates			(789)	(995)	(1,312)
State tax expense, net of federal benefit			197	142	150
Settlements and releases from judicial decisions and statute expirations, net			(132)	(252)	(189)
Domestic production activity deduction			0	(87)	(119)
Federal research and development credit			(158)	(174)	(127)
Stock-based compensation			(201)	(302)	(149)
Other, net			81	6	(114)
Total provision for income taxes			$ 1,185	$ 8,837	$ 2,228