Impact on Earnings from Interest Rate Swaps (Details) (Interest Rate Swap, USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Other Comprehensive Income
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(loss) recognized in accumulated other comprehensive income	$ (486)	$ (1,813)	$ (1,638)	$ (3,733)
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(loss) reclassified from accumulated other comprehensive income (effective portion)	(501)	(896)	(1,518)	(2,473)
Other Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(loss) recognized in income (ineffective portion)	$ 5	$ (22)	$ 18	$ (19)