Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2016
Deferred income taxes and other long-term liabilities
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan liabilities	$ 641	$ 569
Liability related to the unfunded pension plan	70	107
General and Administrative Expense
Defined Contribution Plan Disclosure [Line Items]
401(k) employee savings plans, expenses	80	75	$ 72
General and Administrative Expense | Profit Sharing Plan
Defined Contribution Plan Disclosure [Line Items]
Contribution and cash award expenses included in selling and administrative expenses	59	68	64
General and Administrative Expense | Long Term Incentive Plan
Defined Contribution Plan Disclosure [Line Items]
Contribution and cash award expenses included in selling and administrative expenses	$ 33	$ 21	$ 85