Summary of Significant Accounting Policies (Details 4) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Sales Returns and Allowances [Member]
Rollforward of activity in the Company's allowance for doubtful accounts and its aggregate reserves for returns, discounts, end-of-season markdowns and operational chargebacks
Beginning reserve balance	$ 184.0	$ 165.5	$ 204.7	$ 176.5
Amount charged against revenue to increase reserve	72.6	168.6	83.9	282.5
Amount credited against customer accounts to decrease reserve	(88.2)	(135.8)	(122.1)	(261.7)
Foreign currency translation	3.5	(2.8)	5.4	(1.8)
Ending reserve balance	171.9	195.5	171.9	195.5
Allowance for Doubtful Accounts
Rollforward of activity in the Company's allowance for doubtful accounts and its aggregate reserves for returns, discounts, end-of-season markdowns and operational chargebacks
Beginning reserve balance	55.9	15.0	71.5	15.7
Amount recorded to expense to increase (decrease) reserve	(8.9)	1.4	(25.4)	1.5
Amount credited against customer accounts to decrease reserve	(1.6)	(0.4)	(1.6)	(1.4)
Foreign currency translation	0.9	(0.4)	1.8	(0.2)
Ending reserve balance	$ 46.3	$ 15.6	$ 46.3	$ 15.6