COMMITMENTS - Schedule of Aircraft Purchase Commitments (Details)	3 Months Ended
Aug. 31, 2025 AirCraft
Schedule of Aircraft Commitments [Line Items]
2026	24
2027	13
2028	9
2029	4
2030	2
Thereafter	0
Total	52
Cessna SkyCourier 408
Schedule of Aircraft Commitments [Line Items]
2026	15
2027	4
2028	0
2029	0
2030	0
Thereafter	0
Total	19
ATR 72-600F
Schedule of Aircraft Commitments [Line Items]
2026	3
2027	4
2028	4
2029	4
2030	2
Thereafter	0
Total	17
B767F
Schedule of Aircraft Commitments [Line Items]
2026	6
2027	0
2028	0
2029	0
2030	0
Thereafter	0
Total	6
B777F
Schedule of Aircraft Commitments [Line Items]
2026	0
2027	5
2028	5
2029	0
2030	0
Thereafter	0
Total	10

The total number of aircraft committed to be purchased.

No definition available.

Name:	fdx_AircraftPurchaseObligation
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date after the fourth fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryDueAfterFourthFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date in the first fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryDueInFirstFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date in the fourth fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryDueInFourthFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date in the second fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryDueInSecondFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date in the third fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryDueInThirdFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft committed to be purchased with a delivery date in the remainder of current fiscal year.

+ References

No definition available.

+ Details

Name:	fdx_AircraftPurchaseObligationWithDeliveryWithinRemainderOfFiscalYear
Namespace Prefix:	fdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Schedule of Aircraft Commitments [Line Items]

+ References

No definition available.

+ Details

Name:	fdx_ScheduleOfAircraftCommitmentsLineItems
Namespace Prefix:	fdx_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=fdx_CessnaSkyCourier408Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=fdx_ATR72600FreighterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=fdx_Boeing767300FreighterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=fdx_Boeing777FreighterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: