Term B Loan - Schedule of Interest Expense (Details) - Senior Notes - Term B Loan - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Debt Instrument [Line Items]
Contractual interest expense	$ 2,314	$ 2,275	$ 4,659	$ 4,381
Amortization of debt issuance costs and debt discount	205	205	410	409
Total	$ 2,519	$ 2,480	$ 5,069	$ 4,790

Amount of amortization expense attributable to debt issuance costs.

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