Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 31, 2015	Aug. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 12,279	$ 11,684
Operating Income	1,144	1,062
FedEx Express Segment [Member]
Segment Reporting Information [Line Items]
Revenues	6,591	6,862
Operating Income	545	377
FedEx Ground Segment [Member]
Segment Reporting Information [Line Items]
Revenues	3,830	2,960
Operating Income	537	545
FedEx Freight Segment [Member]
Segment Reporting Information [Line Items]
Revenues	1,601	1,609
Operating Income	132	168
FedEx Services Segment [Member]
Segment Reporting Information [Line Items]
Revenues	390	374
Eliminations, corporate and other
Segment Reporting Information [Line Items]
Revenues	(133)	(121)
Operating Income	$ (70)	$ (28)