NET (LOSS) INCOME ATTRIBUTABLE TO COTY INC. PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Amounts attributable to Coty Inc.:
Net (loss) income attributable to Coty Inc.	$ (123.6)	$ 23.7	$ (55.7)	$ 106.6
Convertible Series B Preferred Stock dividends	(3.3)	(3.3)	(6.6)	(6.6)
Net (loss) income attributable to common stockholders	$ (126.9)	$ 20.4	$ (62.3)	$ 100.0
Weighted-average common shares outstanding:
Weighted-average common shares outstanding—Basic (in shares)	876.8	871.4	874.8	869.6
Effect of dilutive stock options and Series A Preferred Stock (in shares)	0.0	0.0	0.0	0.0
Effect of restricted stock and RSUs (in shares)	0.0	3.8	0.0	5.6
Effect of Convertible Series B Preferred Stock (in shares)	0.0	0.0	0.0	0.0
Effect of Forward Repurchase Contracts (in shares)	0.0	0.0	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	876.8	875.2	874.8	875.2
Earnings per common share:
Earnings per common share - basic (in dollars per share)	$ (0.14)	$ 0.02	$ (0.07)	$ 0.11
Earnings per common share - diluted (in dollars per share)	$ (0.14)	$ 0.02	$ (0.07)	$ 0.11
Convertible Series B Preferred Stock dividends	$ 3.3	$ 3.3	$ 6.6	$ 6.6
Antidilutive​ fair market value losses (gains)	$ 38.6	$ 96.5	$ 65.1	$ 128.8
Stock Options and Series A Preferred Stock
Earnings per common share:
Anti-dilutive shares (in shares)	3.4	3.5	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)	21.5	13.7	17.4	6.8
Series B Preferred Stock
Earnings per common share:
Anti-dilutive shares (in shares)	0.0	0.0	0.0	0.0
Forward Contracts
Earnings per common share:
Anti-dilutive shares (in shares)	0.0	0.0	0.0	0.0