EMPLOYEE BENEFIT PLANS AND OTHER POST-RETIREMENT BENEFITS - Funding and Cash Flows - Contributions (Details) - Qualified Plan $ in Millions	12 Months Ended
May 31, 2020 USD ($)
Contributions
Employer contributions	$ 3.8
Employer contributions, fiscal year 2021	$ 3.4
Defined benefit plan, type	us-gaap:PensionPlansDefinedBenefitMember

Amount of contribution received by defined benefit plan from employer which increases plan assets.

Indicates type of defined benefit plan. Includes, but is not limited to, pension plan, other postretirement plan and special and contractual termination benefits payable upon retirement.

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+ Details