Acquisition (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011	Jan. 13, 2012
Acquisition (Textual) [Abstract]
Name of acquired entity			ILX Lightwave Corporation
Date of acquisition			Jan. 13, 2012
Purchase price of the acquisition					$ 9.0
Initial purchase price					9.3
Purchase price deposited at closing into escrow until July 12, 2013					1.2
Escrow Expiration Date					July 12, 2013
Net asset adjustment					0.3
Business combination, transaction costs incurred					0.1
PPT goodwill allocation					3.8
Pro forma decrease in amortization expense	0.1		0.2
Pro forma increase in amortization expense		0.2		0.6
Charges to cost of sales related to inventory added back to pro forma net income			0.1
Pro forma transaction costs			$ 0.4