REVENUE RECOGNITION (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jul. 01, 2018	Jun. 30, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Property and equipment, net	$ 1,648.0		$ 1,674.6
Deferred income taxes	219.0		108.0
Other noncurrent assets	196.7		306.4
Accrued expenses and other current liabilities	1,737.7		1,865.1
Deferred income taxes	841.1		841.3
Net revenues	2,031.3	$ 2,238.3
Selling, general and administrative expenses	1,122.3	1,191.1
Net loss	(10.1)	(16.1)
Net loss attributable to Coty Inc.	$ (12.1)	$ (19.7)
Basic (in dollars per share)	$ (0.02)	$ (0.03)
Diluted (in dollars per share)	$ (0.02)	$ (0.03)
Accumulated deficit	$ (769.1)		$ (644.4)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Property and equipment, net				$ 1,680.8
Deferred income taxes				107.4
Other noncurrent assets				299.5
Accrued expenses and other current liabilities				1,844.4
Deferred income taxes				842.5
Net revenues	2,038.5
Selling, general and administrative expenses	1,123.4
Net loss	(5.2)
Net loss attributable to Coty Inc.	$ (7.6)
Basic (in dollars per share)	$ (0.01)
Diluted (in dollars per share)	$ (0.01)
Accumulated deficit				(626.2)
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Property and equipment, net				(6.2)
Deferred income taxes				0.6
Other noncurrent assets				6.9
Accrued expenses and other current liabilities				20.7
Deferred income taxes				(1.2)
Net revenues	$ 7.2
Selling, general and administrative expenses	1.1
Net loss	4.9
Net loss attributable to Coty Inc.	$ 4.5
Basic (in dollars per share)	$ 0.01
Diluted (in dollars per share)	$ 0.01
Accumulated deficit				$ (18.2)