Derivative Instruments and Hedging Activities Part 2 (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Restricted cash related to open futures contracts	$ 2,600,000		$ 2,600,000
Fair Value Hedges [Member] | Cost of goods sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on designated and qualifying fair value hedges	2,344,000
Commodity contracts [Member] | Cost of goods sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on designated and qualifying fair value hedges	(2,261,000)
Commodity contracts [Member] | Fair Value Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Accumulated OCI (Effective Portion), Net of Tax	562,000	(2,386,000)	455,000	(1,593,000)
Commodity contracts [Member] | Fair Value Hedges [Member] | Cost of goods sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss Reclassified from Accumulated OCI into Income (Effective Portion), Net of Tax	$ (2,000)	$ (790,000)	$ 428,000	$ (1,816,000)