CONDENSED CONSOLIDATED STATEMENTS OF EQUITY AND REDEEMABLE NONCONTROLLING INTERESTS (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Preferred Stock	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Additional Paid-in Capital	(Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total Coty Inc. Stockholders’ Equity	Noncontrolling Interests
Balance as previously reported (in shares) at Jun. 30, 2016		1.7	138.7	262.0				63.6
Balance, beginning of period at Jun. 30, 2016	$ 367.1	$ 0.0	$ 1.4	$ 2.6	$ 2,038.4	$ (37.0)	$ (239.7)	$ (1,405.5)	$ 360.2	$ 6.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Preferred Stock (in shares)		2.5
Issuance of Preferred Stock		$ 0.0
Exercise of employee stock options and restricted stock units (in shares)			2.2
Exercise of employee stock options and restricted stock units	19.5		$ 0.0		19.5				19.5
Share-based compensation expense	15.2				15.2				15.2
Dividends ($0.375 per Common Share)	(281.2)				(281.2)				(281.2)
Net income (loss)	(103.2)					(117.4)			(117.4)	14.2
Other comprehensive income	45.8						46.0		46.0	(0.2)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	0.0				0.0				0.0
Adjustment of redeemable noncontrolling interests to redemption value	(24.9)				(24.9)				(24.9)
Conversion of Class B to Class A Common Stock (in shares)			262.0	(262.0)
Conversion of Class B to Class A Common Stock	0.0		$ 2.6	$ (2.6)					0.0
Purchase of Class A Common Stock (in shares)								1.4
Purchase of Class A Common Stock	(36.3)							$ (36.3)	(36.3)
Issuance of Class A Common Stock for business combination (in shares)			409.7
Issuance of Class A Common Stock for business combination	9,628.6		$ 4.1		9,624.5				9,628.6
Balance, end of period (in shares) at Mar. 31, 2017		4.2	812.6	0.0				65.0
Balance, end of period at Mar. 31, 2017	9,630.6	$ 0.0	$ 8.1	$ 0.0	11,391.5	(154.4)	(193.7)	$ (1,441.8)	9,609.7	20.9
BALANCE as previously reported—July 1, 2017 at Jun. 30, 2016	73.3
Increase (Decrease) in Redeemable Noncontrolling Interests [Roll Forward]
Net income (loss)	5.7
Distribution to noncontrolling interests, net	(7.5)
Redeemable noncontrolling interests issued during the period	410.9
Adjustment of redeemable noncontrolling interests to redemption value	(24.9)
Repurchase of redeemable noncontrolling interests	(0.9)
Balance, end of period at Mar. 31, 2017	506.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustment due to the adoption of ASU 2016-09 (see Note 2)	8.3					8.3			8.3
BALANCE as adjusted—July 1, 2017	9,326.0	$ 0.0	$ 8.1		11,203.2	(450.9)	4.4	$ (1,441.8)	9,323.0	3.0
Balance as previously reported (in shares) at Jun. 30, 2017		4.2	812.9					65.0
Balance, beginning of period at Jun. 30, 2017	9,317.7	$ 0.0	$ 8.1		11,203.2	(459.2)	4.4	$ (1,441.8)	9,314.7	3.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Preferred Stock (in shares)		1.0
Issuance of Preferred Stock	0.0	$ 0.0							0.0
Stock cancelled during period (in shares)		(0.2)
Cancellation of Preferred Stock	0.0	$ 0.0							0.0
Exercise of employee stock options and restricted stock units (in shares)			2.6
Exercise of employee stock options and restricted stock units	20.0		$ 0.0		20.0				20.0
Shares withheld for employee taxes	(3.5)				(3.5)				(3.5)
Share-based compensation expense	25.8				25.8				25.8
Dividends ($0.375 per Common Share)	(283.3)				(283.3)				(283.3)
Net income (loss)	9.5					12.5			12.5	(3.0)
Other comprehensive income	532.0						531.7		531.7	0.3
Dilution of redeemable noncontrolling interest due to additional contribution (See Note 16)	17.0				17.0				17.0
Additional redeemable noncontrolling interests due to employee grants (See Note 16)	(7.4)				(7.4)				(7.4)
Adjustment of redeemable noncontrolling interests to redemption value	(136.5)				(136.5)				(136.5)
Balance, end of period (in shares) at Mar. 31, 2018		5.0	815.5					65.0
Balance, end of period at Mar. 31, 2018	9,499.6	$ 0.0	$ 8.1		10,835.3	$ (438.4)	$ 536.1	$ (1,441.8)	9,499.3	$ 0.3
BALANCE as previously reported—July 1, 2017 at Jun. 30, 2017	551.1
Increase (Decrease) in Redeemable Noncontrolling Interests [Roll Forward]
Net income (loss)	32.9
Distribution to noncontrolling interests, net	(45.7)
Dilution of redeemable noncontrolling interest due to additional contribution (See Note 16)	(17.0)				$ (17.0)				$ (17.0)
Redeemable noncontrolling interests issued during the period	7.4
Proceeds from redeemable noncontrolling interests	0.2
Adjustment of redeemable noncontrolling interests to redemption value	136.5
Balance, end of period at Mar. 31, 2018	$ 665.4