Business Segments and Disaggregated Revenue - Schedule of Revenue by Service Type (Details) - USD ($) $ in Millions		12 Months Ended
		May 31, 2024	May 31, 2023	May 31, 2022
Entity Wide Information Revenue From External Customer [Line Items]
Revenues	[1]	$ 87,693	$ 90,155	$ 93,512
Operating Segments [Member] | FedEx Express Segment [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		40,857	42,743	45,814
Operating Segments [Member] | FedEx Express Segment [Member] | U.S. overnight box [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		8,689	8,916	9,084
Operating Segments [Member] | FedEx Express Segment [Member] | U.S. overnight envelope [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		1,854	1,980	1,971
Operating Segments [Member] | FedEx Express Segment [Member] | U.S. deferred [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		4,928	5,128	5,330
Operating Segments [Member] | FedEx Express Segment [Member] | Total U.S. domestic package revenue [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		15,471	16,024	16,385
Operating Segments [Member] | FedEx Express Segment [Member] | International priority [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		9,455	10,939	12,130
Operating Segments [Member] | FedEx Express Segment [Member] | International economy [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		4,273	2,911	2,838
Operating Segments [Member] | FedEx Express Segment [Member] | Total international export package revenue [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		13,728	13,850	14,968
Operating Segments [Member] | FedEx Express Segment [Member] | International domestic [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues	[2]	4,178	4,043	4,340
Operating Segments [Member] | FedEx Express Segment [Member] | Total package revenue [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		33,377	33,917	35,693
Operating Segments [Member] | FedEx Express Segment [Member] | U.S. freight [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		2,418	2,906	3,041
Operating Segments [Member] | FedEx Express Segment [Member] | International priority freight [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		2,205	3,060	3,840
Operating Segments [Member] | FedEx Express Segment [Member] | International Economy Freight
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		1,677	1,510	1,653
Operating Segments [Member] | FedEx Express Segment [Member] | International Airfreight [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		126	166	177
Operating Segments [Member] | FedEx Express Segment [Member] | Total freight revenue [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		6,426	7,642	8,711
Operating Segments [Member] | FedEx Express Segment [Member] | Other [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		1,054	1,184	1,410
Operating Segments [Member] | FedEx Ground Segment [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		34,256	33,507	33,232
Operating Segments [Member] | FedEx Freight Segment [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		9,082	9,632	9,532
Operating Segments [Member] | FedEx Services Segment [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues		260	301	253
Corporate, Other and Eliminations [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Revenues	[3]	$ 3,238	$ 3,972	$ 4,681

[1] 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, operating lease right-of-use assets, 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.

[2] International domestic revenue relates to our intra-country operations.

[3] Includes the FedEx Office, FedEx Logistics, and FedEx Dataworks operating segments.