NET INCOME ATTRIBUTABLE TO COTY INC. PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Amounts attributable to Coty Inc.:
Net income attributable to Coty Inc.	$ 67.9	$ 82.9
Convertible Series B Preferred Stock dividends	(3.3)	(3.3)
Net income attributable to common stockholders	$ 64.6	$ 79.6
Weighted-average common shares outstanding:
Weighted-average common shares outstanding—Basic (in shares)	872.8	867.9
Effect of dilutive stock options and Series A Preferred Stock (in shares)	0.0	0.0
Effect of restricted stock and RSUs (in shares)	3.5	7.4
Effect of Convertible Series B Preferred Stock (in shares)	0.0	0.0
Effect of Forward Repurchase Contracts (in shares)	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	876.3	875.3
Earnings per common share:
Earnings per common share - basic (in dollars per share)	$ 0.07	$ 0.09
Earnings per common share - diluted (in dollars per share)	$ 0.07	$ 0.09
Convertible Series B Preferred Stock dividends	$ 3.3	$ 3.3
Antidilutive​ fair market value losses (gains)	$ 26.5	$ 24.6
Stock Options and Series A Preferred Stock
Earnings per common share:
Anti-dilutive shares (in shares)	3.4	3.5
Series A Preferred Stock
Earnings per common share:
Anti-dilutive shares (in shares)	0.0
RSUs
Earnings per common share:
Anti-dilutive shares (in shares)	13.3	0.0
Series B Preferred Stock
Earnings per common share:
Anti-dilutive shares (in shares)	0.0	0.0
Forward Contracts
Earnings per common share:
Anti-dilutive shares (in shares)	0.0	0.0