Sales, Gross Profit and Gross Profit Margin by Reportable Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 26, 2014	Sep. 27, 2013
Segment Reporting Information [Line Items]
Sales	$ 94,656	$ 79,858	$ 270,694	$ 234,698
Gross Profit	39,683	34,161	110,439	98,031
Gross profit margin percentage	41.90%	42.80%	40.80%	41.80%
Laser Products
Segment Reporting Information [Line Items]
Sales	45,806	44,714	131,494	123,311
Gross Profit	20,269	19,252	54,437	51,436
Gross profit margin percentage	44.20%	43.10%	41.40%	41.70%
Medical Technologies
Segment Reporting Information [Line Items]
Sales	32,680	19,718	89,838	65,410
Gross Profit	12,945	7,535	35,672	25,271
Gross profit margin percentage	39.60%	38.20%	39.70%	38.60%
Precision Motion
Segment Reporting Information [Line Items]
Sales	16,170	15,426	49,362	45,977
Gross Profit	6,776	7,429	21,141	21,487
Gross profit margin percentage	41.90%	48.20%	42.80%	46.70%
Corporate, Shared Services and Unallocated
Segment Reporting Information [Line Items]
Gross Profit	$ (307)	$ (55)	$ (811)	$ (163)