Business Segment Information (Details 4) - USD ($) $ in Millions		3 Months Ended												12 Months Ended
		May 31, 2016		Feb. 29, 2016	[1]	Nov. 30, 2015	[1]	Aug. 31, 2015	May 31, 2015		Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	May 31, 2016	May 31, 2015	May 31, 2014
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues		$ 12,979	[1]	$ 12,654		$ 12,453		$ 12,279	$ 12,114	[2]	$ 11,716	$ 11,939	$ 11,684	$ 50,365	$ 47,453	$ 45,567
Assets Noncurrent		34,075							26,196					34,075	26,196	23,387
U.S. [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues														38,070	34,216	32,259
Assets Noncurrent		26,047							23,582					26,047	23,582	20,658
International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Assets Noncurrent		$ 8,028							$ 2,614					8,028	2,614	2,729
FedEx Express Segment [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues														26,451	27,239	27,121
FedEx Express Segment [Member] | International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3]													11,672	12,772	12,916
FedEx Ground Segment [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues														16,574	12,984	11,617
FedEx Ground Segment [Member] | International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3]													383	311	248
FedEx Freight Segment [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues														6,200	6,191	5,757
FedEx Freight Segment [Member] | International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3]													137	142	130
FedEx Services Segment [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues														1,593	1,545	1,536
FedEx Services Segment [Member] | International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3]													10	12	14
Other international revenue [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3],[4]													93
Total international revenue [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	[3]													$ 12,295	$ 13,237	$ 13,308

[1] The fourth quarter of 2016 includes a $1.5 billion retirement plans mark-to-market loss and TNT Express transaction, financing and integration planning expenses and immaterial financial results from the time of acquisition totaling $79 million. In addition, the fourth quarter of 2016 includes a $76 million favorable tax impact from an internal corporate restructuring to facilitate the integration of FedEx Express and TNT Express and $11 million of expenses related to independent contractor litigation matters at FedEx Ground. The third quarter of 2016 includes provisions related to independent contractor litigation matters at FedEx Ground for $204 million and expenses related to the settlement of a U.S. Customs and Border Protection notice of action in the amount of $69 million, as well as TNT Express transaction, financing and integration planning expenses of $25 million. The second quarter of 2016 includes provisions related to independent contractor litigation matters at FedEx Ground for $41 million and $19 million of TNT Express transaction, financing and integration planning expenses.

[2] The fourth quarter of 2015 includes a $2.2 billion retirement plans mark-to-market loss, $276 million of impairment and related charges resulting from the decision to permanently retire and adjust the retirement schedule of certain aircraft and related engines at FedEx Express and a $197 million reserve increase due to the settlement of a legal matter at FedEx Ground.

[3] International revenue includes shipments that either originate in or are destined to locations outside the United States, which could include U.S. payors. Noncurrent assets include property and equipment, goodwill and other long-term assets. Our flight equipment is registered in the U.S. and is included as U.S. assets; however, many of our aircraft operate internationally.

[4] Includes TNT Express’s revenue from the time of acquisition (May 25, 2016).