NET INCOME ATTRIBUTABLE TO COTY INC. PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net loss attributable to Coty Inc.	$ (12.1)	$ (19.7)
Weighted-average common shares outstanding:
Weighted-average common shares outstanding—basic (in shares)	750.8	748.6
Effect of dilutive stock options and Series A Preferred Stock (in shares)	0.0	0.0
Effect of restricted stock and RSUs (in shares)	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	750.8	748.6
Net loss attributable to Coty Inc. per common share:
Basic (in dollars per share)	$ (0.02)	$ (0.03)
Diluted (in dollars per share)	$ (0.02)	$ (0.03)