Selected Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 29, 2015	Dec. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Mar. 30, 2014	Dec. 29, 2013	Sep. 29, 2013	Jun. 30, 2013	Mar. 29, 2015	Mar. 30, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]
Sales	$ 93,281	$ 83,825	$ 88,881	$ 98,036	$ 85,223	$ 81,697	$ 86,599	$ 94,744	$ 364,023	$ 348,263	$ 350,387
Gross profit	15,531	13,642	18,122	18,496	14,249	13,550	16,570	17,231	65,791	61,600	56,936
Selling, general, and administrative expenses	9,532	8,697	8,271	8,875	8,080	8,167	8,293	8,970	35,375	33,510	31,606
Operating income	5,999	4,945	9,851	9,621	6,169	5,383	8,277	8,261	30,416	28,090	25,330
Net income	$ 3,900	$ 3,146	$ 6,147	$ 6,021	$ 4,295	$ 3,480	$ 5,207	$ 5,112	$ 19,214	$ 18,094	$ 17,126
Basic earnings per share (usd per share)	$ 0.37	$ 0.30	$ 0.58	$ 0.57	$ 0.41	$ 0.33	$ 0.49	$ 0.49	$ 1.82	$ 1.72	$ 1.64
Diluted earnings per share (usd per share)	$ 0.37	$ 0.30	$ 0.58	$ 0.57	$ 0.40	$ 0.33	$ 0.49	$ 0.48	$ 1.81	$ 1.71	$ 1.62