Net Periodic Benefit Cost - Defined Benefit Pension Plans (Details) (Pension plans, defined benefit [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Pension plans, defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service costs--increase in benefit obligation earned	$ 47	$ 33	$ 138	$ 100
Interest cost on projected benefit obligation	412	418	1,244	1,253
Expected return on plan assets	(424)	(476)	(1,277)	(1,430)
Settlement loss	0	0	219	0
Amortization of net actuarial loss	259	134	781	401
Amortization of prior service cost	3	3	10	10
Amortization of transition asset	0	(17)	0	(51)
Net pension cost of defined benefit pension plans	297	95	1,115	283
Contributions by employer			786
Estimated future employer contributions in current fiscal year	$ 53		$ 53