Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales	$ 172,916	$ 164,317	$ 348,901	$ 328,214
Cost of sales	105,097	102,399	213,343	204,280
Gross margin	67,819	61,918	135,558	123,934
Operating expenses:
Selling, general and administrative	29,326	27,595	58,901	55,373
Other, net	2,609	8,886	4,775	11,165
Total operating expenses	31,935	36,481	63,676	66,538
Operating income	35,884	25,437	71,882	57,396
Interest expense, net	1,446	1,914	3,157	3,943
Other non-operating expense	336	223	1,370	754
Income before income taxes	34,102	23,300	67,355	52,699
Provision for income taxes	3,991	8,477	9,777	16,067
Net income	$ 30,111	$ 14,823	$ 57,578	$ 36,632
Net income per common share:
Basic (in dollars per share)	$ 1.24	$ 0.62	$ 2.38	$ 1.53
Diluted (in dollars per share)	$ 1.22	$ 0.61	$ 2.34	$ 1.51
Weighted average common shares:
Basic (in shares)	24,325,754	23,946,360	24,233,266	23,875,749
Diluted (in shares)	24,719,056	24,309,593	24,635,146	24,250,740