Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Income Statement [Abstract]
Sales	$ 145,324	$ 125,395	$ 295,124	$ 259,126
Cost of sales	(119,552)	(101,280)	(240,895)	(209,012)
Gross profit	25,772	24,115	54,229	50,114
Selling, general and administrative expenses	(14,941)	(14,828)	(29,920)	(30,594)
Operating income	10,831	9,287	24,309	19,520
Interest expense, net	(733)	(816)	(1,669)	(1,566)
Income before income taxes	10,098	8,471	22,640	17,954
Income tax expense	(2,689)	(3,261)	(6,108)	(6,913)
Net income	$ 7,409	$ 5,210	$ 16,532	$ 11,041
Weighted average number of shares outstanding - basic	10,675,833	10,605,629	10,662,210	10,594,309
Weighted average number of shares outstanding - diluted	10,719,059	10,650,585	10,714,381	10,641,731
Basic earnings per share
Basic earnings per share	$ 0.69	$ 0.49	$ 1.55	$ 1.04
Diluted earnings per share
Diluted earnings per share	0.69	0.49	1.54	1.04
Cash dividends declared per common share	$ 0.225	$ 0.44	$ 0.225	$ 0.44