Other Accrued Expenses - Schedule of Accrued Severance (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Restructuring Reserve [Roll Forward]
Severance	$ 9.9	$ 14.9	$ 11.9
Severance [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	6.6	4.4
Accruals	9.9	14.9
Payments	(12.3)	(12.7)
Ending balance	4.2	6.6	$ 4.4
Cost Reduction Programs [Member]
Restructuring Reserve [Roll Forward]
Severance	$ 7.4	$ 12.9

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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