Non-Operating Income and Deductions, Net (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012
Non-Operating Deductions, Net [Abstract]
Interest income	$ 700,000	$ 800,000	$ 1,400,000	$ 1,800,000
Interest expense	(800,000)	(800,000)	(1,600,000)	(1,600,000)
Foreign exchange gains (losses)	(1,300,000)	(300,000)	(600,000)	(700,000)
Other deductions	(100,000)	(500,000)	(500,000)	(900,000)
Non-operating deductions, net	$ (1,472,000)	$ (767,000)	$ (1,339,000)	$ (1,366,000)