Acquisitions - Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	May 31, 2016	Sep. 30, 2017	Apr. 01, 2017
Business Acquisition [Line Items]
Goodwill		$ 119.7	$ 119.7
Michael Kors (HK) Limited
Business Acquisition [Line Items]
Cash and cash equivalents	$ 19.4
Accounts receivable	22.3
Inventory	36.1
Other current assets	5.5
Current assets	83.3
Property and equipment	46.6
Goodwill	96.5
Favorable lease assets	1.8
Deferred tax assets	7.8
Other assets	6.6
Total assets acquired	643.7
Accounts payable	8.9
Short-term debt	5.8
Other current liabilities	27.8
Current liabilities	42.5
Unfavorable lease liabilities	4.8
Deferred tax liabilities	92.3
Other liabilities	4.1
Total liabilities assumed	143.7
Fair value of net assets acquired	500.0
Fair value of acquisition consideration	500.0
Reacquired rights | Michael Kors (HK) Limited
Business Acquisition [Line Items]
Intangible assets	400.4
Customer relationships | Michael Kors (HK) Limited
Business Acquisition [Line Items]
Intangible assets	$ 0.7