Segments - Reconciling Information Between Reportable Segments' Operating Earnings and Consolidated Earnings Before Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment operating earnings	$ 11,159	$ 7,682	$ 24,764	$ 19,158
Interest expense	(849)	(584)	(2,843)	(1,869)
Interest income	442	425	1,301	1,341
Other income	706	763	694	297
Earnings before income taxes	10,392	7,408	13,933	14,218
Components and Sensors segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment operating earnings	10,176	5,307	25,946	13,690
Restructuring and restructuring-related charges	(927)	(365)	(8,821)	(1,604)
EMS [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment operating earnings	983	2,375	(1,182)	5,468
Restructuring and restructuring-related charges	$ (139)	$ (513)	$ (1,162)	$ (3,105)