EMPLOYEE BENEFIT PLANS AND OTHER POST-RETIREMENT BENEFITS - Payment From Pension Plan Assets (Details) $ in Millions	12 Months Ended
May 31, 2020 USD ($)
EMPLOYEE BENEFIT PLANS AND OTHER POST-RETIREMENT BENEFITS
Payment for settlement from Rabbi trust plan assets	$ 0.4

The amount of plan settlement payments made to certain participants from Rabbi trust plan assets.

No definition available.

Name:	lw_DefinedBenefitPlanPaymentForSettlementFromRabbiTrustPlanAssets
Namespace Prefix:	lw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration