NET LOSS ATTRIBUTABLE TO COTY INC. PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net loss attributable to Coty Inc.	$ (3,784.2)	$ (168.8)	$ (422.2)
Weighted-average common shares outstanding:
Weighted-average common shares outstanding—Basic (in shares)	751.2	749.7	642.8
Effect of dilutive stock options and Series A Preferred Stock (in shares)	0.0	0.0	0.0
Effect of restricted stock and RSUs (in shares)	0.0	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	751.2	749.7	642.8
Net loss attributable to Coty Inc. per common share:
Basic (dollars per shares)	$ (5.04)	$ (0.23)	$ (0.66)
Diluted (dollars per shares)	$ (5.04)	$ (0.23)	$ (0.66)