General - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
	May 31, 2018	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017	Jan. 26, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Gross contract assets related to in-transit packages	$ 542	$ 600		$ 600
Contract assets net of deferred unearned revenue	363	423		423
Contract liabilities related to advance payments from customers	13	9		$ 9
Payment terms of customer contracts				Under the typical payment terms of our customer contracts, the customer pays at periodic intervals (e.g., every 15 days, 30 days, 45 days, etc.) for shipments included on invoices received. It is not customary business practice to extend payment terms past 90 days, and as such, we do not have a practice of including a significant financing component within our revenue contracts with customers.
Stock-based compensation		40	$ 41	$ 108	$ 103
Provisional benefit related to remeasurement of net U.S. deferred tax liability, income tax expense amount recognized		4
Provisional benefit related to remeasurement of net U.S. deferred tax liability	$ (1,150)
Lease liability and related right-of-use asset		$ 13,000		$ 13,000
Stock Repurchase Program Number Of Shares Authorized To Be Repurchased						25,000,000
Number of Shares Repurchased		2,800,000		5,400,000
Treasury Stock Acquired, Average Cost Per Share		$ 228.35		$ 233.44
Payments for Repurchase of Common Stock		$ 646		$ 1,271	$ 270
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased		6,300,000		6,300,000
Dividends Payable, Date Declared				Nov. 16, 2018
Dividends Payable Amount Per Share		$ 0.65		$ 0.65
Dividends Payable, Date To Be Paid				Jan. 02, 2019
Dividends Payable, Date Of Record				Dec. 10, 2018