NET LOSS ATTRIBUTABLE TO COTY INC. PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Net loss from continuing operations	$ (1,093.9)	$ (3,905.2)	$ (403.3)
Convertible Series B Preferred Stock dividends	(6.5)	0.0	0.0
Net loss from continuing operations attributable to common stockholders	(1,100.4)	(3,905.2)	(403.3)
Net income from discontinued operations	87.2	121.0	234.5
Net loss attributable to common stockholders	$ (1,013.2)	$ (3,784.2)	$ (168.8)
Weighted-average common shares outstanding:
Weighted-average common shares outstanding—Basic (in shares)	759.1	751.2	749.7
Effect of dilutive stock options and Series A/A-1 Preferred Stock (in shares)	0.0	0.0	0.0
Effect of restricted stock and RSUs (in shares)	0.0	0.0	0.0
Effect of Convertible Series B Preferred Shares (in shares)	0.0	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	759.1	751.2	749.7
(Loss) from continuing operations per common share - basic (in dollars per share)	$ (1.45)	$ (5.20)	$ (0.54)
(Loss) from continuing operations per common share - diluted (in dollars per share)	(1.45)	(5.20)	(0.54)
Earnings from discontinued operations - basic (in dollars per share)	0.12	0.16	0.31
Earnings from discontinued operations - diluted (in dollars per share)	0.12	0.16	0.31
(Loss) per common share - basic (in dollars per share)	(1.33)	(5.04)	(0.23)
(Loss) per common share - diluted (in dollars per share)	$ (1.33)	$ (5.04)	$ (0.23)