Income Taxes (Details 3) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	May 31, 2016	May 31, 2016	May 31, 2015	May 31, 2014
IncomeTax Expense Benefit Continuing Operations Income Tax Reconciliation [Abstract]
Taxes computed at federal statutory rate		$ 959	$ 569	$ 1,280
State and local income taxes, net of federal benefit		33	36	90
Foreign operations		(50)	(43)	(38)
Internal restructuring	$ 76	(76)
TNT Express acquisition costs		40
Other, net		14	15	2
PROVISION FOR INCOME TAXES		$ 920	$ 577	$ 1,334