Selected Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
	Mar. 30, 2014	Dec. 29, 2013	Sep. 29, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 30, 2012	Sep. 30, 2012	Jul. 01, 2012	Mar. 30, 2014	Mar. 31, 2013	Apr. 01, 2012
Segment Reporting Information [Line Items]
Sales	$ 85,223,000	$ 81,697,000	$ 86,599,000	$ 94,744,000	$ 87,601,000	$ 85,527,000	$ 87,160,000	$ 90,099,000	$ 348,263,000	$ 350,387,000	$ 343,834,000
Gross profit	14,249,000	13,550,000	16,570,000	17,231,000	14,307,000	8,126,000	19,196,000	15,307,000	61,600,000	56,936,000	65,868,000
Selling, general, and administrative expenses	8,080,000	8,167,000	8,293,000	8,970,000	8,307,000	7,617,000	7,455,000	8,227,000	33,510,000	31,606,000	30,759,000
Operating income	6,169,000	5,383,000	8,277,000	8,261,000	6,000,000	509,000	11,741,000	7,080,000	28,090,000	25,330,000	35,109,000
Income from continuing operations, net of tax	4,295,000	3,480,000	5,207,000	5,112,000	4,165,000	1,348,000	7,230,000	4,365,000	18,094,000	17,108,000	21,628,000
Income from discontinued operations, net of tax	0	0	0	0	0	0	0	18,000	0	18,000	1,057,000
Net income	4,295,000	3,480,000	5,207,000	5,112,000	4,165,000	1,348,000	7,230,000	4,383,000	18,094,000	17,126,000	22,685,000
Basic earnings per share (usd per share)	$ 0.41	$ 0.33	$ 0.49	$ 0.49	$ 0.40	$ 0.13	$ 0.69	$ 0.42	$ 1.72	$ 1.64	$ 2.19
Diluted earnings per share (usd per share)	$ 0.40	$ 0.33	$ 0.49	$ 0.48	$ 0.39	$ 0.13	$ 0.69	$ 0.42	$ 1.71	$ 1.62	$ 2.18
Multiemployer pension plan withdrawal charge									0	7,210,000	0
Industrial [Member]
Segment Reporting Information [Line Items]
Sales									244,888,000	248,556,000	251,451,000
Gross profit									32,041,000	28,878,000	40,357,000
Selling, general, and administrative expenses									19,781,000	19,923,000	19,805,000
Operating income									12,260,000	8,955,000	20,552,000
Legal settlement										3,200,000
Multiemployer pension plan withdrawal charge										$ 7,200,000