Goodwill and Intangible Assets - Components of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 29, 2018	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 60,282	$ 10,007
Accumulated amortization	(11,368)	(8,465)
Amortizable intangibles, net	$ 48,914	$ 1,542
Weighted average amortization period, in years	9 years 3 months 18 days	5 years 4 months 24 days
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 47,151	$ 5,739
Accumulated amortization	(7,768)	(5,610)
Amortizable intangibles, net	$ 39,383	$ 129
Weighted average amortization period, in years	9 years 4 months 24 days	4 years 3 months 18 days
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 13,131	$ 4,268
Accumulated amortization	(3,600)	(2,855)
Amortizable intangibles, net	$ 9,531	$ 1,413
Weighted average amortization period, in years	8 years 10 months 24 days	5 years 6 months