Business Segments and Disaggregated Revenue - Schedule of Segment Information (Parenthetical) (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
May 31, 2020 |
Feb. 29, 2020 |
Nov. 30, 2019 |
Aug. 31, 2019 |
May 31, 2019 |
Feb. 28, 2019 |
Nov. 30, 2018 |
Aug. 31, 2018 |
May 31, 2020 |
May 31, 2019 |
May 31, 2018 |
|
| Segment Reporting Information [Line Items] | |||||||||||
| Integration expenses | $ 63 | $ 72 | $ 64 | $ 71 | $ 84 | $ 69 | $ 114 | $ 121 | $ 270 | $ 388 | $ 477 |
| Goodwill and other asset impairment charges | $ 66 | 435 | $ 380 | ||||||||
| Business realignment costs | $ 316 | $ 4 | 320 | ||||||||
| FedEx Office and FedEx Express [Member] | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Goodwill and other asset impairment charges | $ 435 | ||||||||||
| FedEx Ground Segment [Member] | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Ground independent contractor legal expense | $ 46 | $ 46 | |||||||||