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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Mar. 31, 2018
Operating Loss Carryforwards [Line Items]
Effective tax rate	9.80%	15.20%	9.60%	15.70%
Unrecognized tax benefits	$ 124.6		$ 124.6		$ 107.4
Decrease in unrecognized tax benefits is possible in the next twelve months	$ 37.1		$ 37.1
United Kingdom \| Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Provision for incomes taxes at the U.K. statutory tax rate	19.00%