CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2016	Apr. 03, 2015
Income Statement [Abstract]
Revenue	$ 90,316	$ 94,614
Cost of revenue	53,424	54,608
Gross profit	36,892	40,006
Operating expenses:
Research and development and engineering	8,052	8,215
Selling, general and administrative	21,187	22,068
Amortization of purchased intangible assets	2,108	1,889
Restructuring, acquisition and divestiture related costs	2,958	2,437
Total operating expenses	34,305	34,609
Operating income from continuing operations	2,587	5,397
Interest income (expense), net	(1,185)	(1,397)
Foreign exchange transaction gains (losses), net	83	517
Other income (expense), net	743	729
Income from continuing operations before income taxes	2,228	5,246
Income tax provision	322	1,800
Income from continuing operations	1,906	3,446
Consolidated net income	$ 1,906	$ 3,446
Earnings per common share from continuing operations:
Basic	$ 0.05	$ 0.10
Diluted	0.05	0.10
Earnings per common share:
Basic	0.05	0.10
Diluted	$ 0.05	$ 0.10
Weighted average common shares outstanding—basic	34,657	34,506
Weighted average common shares outstanding—diluted	34,853	34,999