CONDENSED CONSOLIDATED STATEMENTS OF EQUITY AND REDEEMABLE NONCONTROLLING INTERESTS - USD ($) $ in Millions	Total	Class A Common Stock	Preferred Stock	Common Stock Class A Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Class A Common Stock	(Accumulated Deficit)	Accumulated Other Comprehensive (Loss) Income	Treasury Stock	Total Coty Inc. Stockholders’ Equity	Total Coty Inc. Stockholders’ Equity Class A Common Stock	Noncontrolling Interests
Balance, beginning of period (in shares) at Jun. 30, 2018			5,000,000.0	815,800,000					65,000,000.0
Balance, beginning of period at Jun. 30, 2018	$ 8,855.2		$ 0.0	$ 8.1	$ 10,750.8		$ (626.2)	$ 158.8	$ (1,441.8)	$ 8,849.7		$ 5.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee stock options and restricted stock units	0.7				0.7					0.7
Share-based compensation expense	6.4				6.4					6.4
Dividends ($0.125 per common share)	(94.0)				(94.0)					(94.0)
Net income (loss)	(10.9)						(12.1)			(12.1)		1.2
Other comprehensive income (loss)	(47.8)							(48.0)		(48.0)		0.2
Distribution to noncontrolling interests, net	(1.3)											(1.3)
Additional redeemable noncontrolling interests due to employee grants (See Note 16)	(1.6)				(1.6)					(1.6)
Adjustment of redeemable noncontrolling interests to the higher of its redemption value or carrying value	37.2				37.2					37.2
Balance, end of period (in shares) at Sep. 30, 2018			5,000,000.0	815,800,000					65,000,000.0
Balance, end of period at Sep. 30, 2018	8,613.1		$ 0.0	$ 8.1	10,699.5		(769.1)	110.8	$ (1,441.8)	8,607.5		5.6
Balance, beginning of period at Jun. 30, 2018	661.3
Redeemable Noncontrolling Interests
Net income (loss)	0.8
Distribution to noncontrolling interests, net	(4.3)
Additional redeemable noncontrolling interests due to employee grants (See Note 16)	1.6
Adjustment of redeemable noncontrolling interests to redemption value	(37.2)
Balance, end of period at Sep. 30, 2018	622.2
Balance, beginning of period (in shares) at Jun. 30, 2019			9,400,000	819,200,000					65,000,000.0
Balance, beginning of period at Jun. 30, 2019	$ 4,593.4		$ 0.1	$ 8.1	10,620.5		(4,541.2)	(58.8)	$ (1,441.8)	4,586.9		6.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Purchase of Class A Common Stock (in shares)	500,000								500,000
Purchase of Class A Common Stock	$ (4.5)								$ (4.5)	(4.5)
Exercise of employee stock options and restricted stock units (in shares)				100,000
Exercise of employee stock options and restricted stock units	0.6				0.6					0.6
Share-based compensation expense	6.2				6.2					6.2
Dividends declared - Cash and Other ($0.125 per common share)	(63.5)				(63.5)					(63.5)
Dividends ($0.125 per common share)	(63.5)				(63.3)
Dividends declared - Stock ($0.125 per common share)	(30.9)				(30.9)					(30.9)
Dividends settled in Shares of Class A Common Stock (in shares)		3,200,000		3,200,000
Dividends settled in Shares of Class A Common Stock		$ 30.9				$ 30.9					$ 30.9
Net income (loss)	55.1						52.3			52.3		2.8
Other comprehensive income (loss)	(124.6)							(124.6)		(124.6)
Adjustments related to the sale of business	6.2				6.2					6.2
Adjustment of redeemable noncontrolling interests to the higher of its redemption value or carrying value	(3.9)				(3.9)					(3.9)
Balance, end of period (in shares) at Sep. 30, 2019			9,400,000	822,500,000					65,500,000
Balance, end of period at Sep. 30, 2019	4,464.3		$ 0.1	$ 8.1	$ 10,566.1		$ (4,489.6)	$ (183.4)	$ (1,446.3)	$ 4,455.0		$ 9.3
Balance, beginning of period at Jun. 30, 2019	451.8
Redeemable Noncontrolling Interests
Net income (loss)	1.2
Distribution to noncontrolling interests, net	(1.9)
Adjustments related to the sale of business	(360.4)
Adjustment of redeemable noncontrolling interests to redemption value	3.9
Balance, end of period at Sep. 30, 2019	$ 94.6