STOCK-BASED COMPENSATION - Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 26, 2018	Aug. 27, 2017
Compensation expense
Stock-settled compensation expense	$ 4.2	$ 2.6
Cash-settled RSUs	2.1	0.9
Share-based compensation expense	6.3	3.5
Income tax benefit	(1.5)	(1.3)
Total compensation expense, net of tax benefit	4.8	2.2
Stock options
Compensation expense
Stock-settled compensation expense	0.1	0.6
Stock-settled restricted stock units
Compensation expense
Stock-settled compensation expense	2.1	1.9
Performance shares
Compensation expense
Stock-settled compensation expense	$ 2.0	$ 0.1

Allocated Share-based Compensation Expense, Cash-settled Restricted Stock Units

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- Definition

Allocated Share-based Compensation Expense, Stock-settled Compensation Expense

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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