GOODWILL AND OTHER IDENTIFIABLE INTANGIBLE ASSETS - Other identifiable intangible assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 26, 2017	Feb. 28, 2016	Feb. 26, 2017	Feb. 28, 2016	May 29, 2016
GOODWILL AND OTHER IDENTIFIABLE INTANGIBLE ASSETS
Weighted Average Useful Life, amortizing intangible assets (in years)			14 years		14 years
Gross Carrying Amount, amortizing intangible assets	$ 34.9		$ 34.9		$ 35.1
Accumulated Amortization, amortizing intangible assets	15.2		15.2		13.5
Gross Carrying Amount, non-amortizing intangible assets	18.0		18.0		18.0
Total intangible assets, excluding goodwill	52.9		52.9		$ 53.1
Amortization expense	$ 0.5	$ 0.5	$ 1.8	$ 1.6