Other Comprehensive Income (Schedule of OCI) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Before-Tax Amount:
Amortization of prior service cost	$ 4	$ 15	$ 12	$ 45
Amortization of actuarial loss	520	1,300	1,559	3,900
Total defined benefit pension plans	524	1,315	1,571	3,945
Loss activity recognized in other comprehensive loss	2,500	(2,700)	2,400	(5,800)
Other Comprehensive income (loss)	(69,446)	1,917	(56,514)	6,580
Tax (Expense) or Benefit:
Amortization of prior service cost	(2)	(6)	(6)	(18)
Amortization of actuarial loss	(201)	(503)	(603)	(1,511)
Total defined benefit pension plans	(203)	(509)	(609)	(1,529)
Loss activity recognized in other comprehensive loss	1,000	1,000	900	2,200
Other Comprehensive income (loss)	(693)	(737)	(401)	(2,544)
Net-of-Tax Amount:
Amortization of prior service cost	2	9	6	27
Amortization of actuarial loss	319	797	956	2,389
Total defined benefit pension plans	321	806	962	2,416
Foreign currency translation	(71,231)	0	(57,547)	0
Net current-period other comprehensive income	(70,139)	1,180	(56,915)	4,036
Natural Gas Swap [Member]
Before-Tax Amount:
Loss reclassified to net income	(70)	95	(427)	(92)
Loss activity recognized in other comprehensive loss	5	(14)	160	73
Total swap derivatives	(65)	81	(267)	(19)
Tax (Expense) or Benefit:
Loss reclassified to net income	27	(37)	166	35
Loss activity recognized in other comprehensive loss	(2)	5	(63)	(28)
Total swap derivatives	25	(32)	103	7
Net-of-Tax Amount:
Loss reclassified to net income	(43)	58	(261)	(57)
Loss activity recognized in other comprehensive loss	3	(9)	97	45
Total swap derivatives	(40)	49	(164)	(12)
Corn Option [Member]
Before-Tax Amount:
Loss reclassified to net income	(1,212)	(2,155)	(2,536)	(3,063)
Loss activity recognized in other comprehensive loss	2,538	2,676	2,265	5,717
Total swap derivatives	1,326	521	(271)	2,654
Tax (Expense) or Benefit:
Loss reclassified to net income	470	835	983	1,187
Loss activity recognized in other comprehensive loss	(985)	(1,031)	(878)	(2,209)
Total swap derivatives	(515)	(196)	105	(1,022)
Net-of-Tax Amount:
Loss reclassified to net income	(742)	(1,320)	(1,553)	(1,876)
Loss activity recognized in other comprehensive loss	1,553	1,645	1,387	3,508
Total swap derivatives	811	325	(166)	1,632
Accumulated Other Comprehensive Income (Loss) [Member]
Before-Tax Amount:
Foreign currency translation	(71,231)	0	(57,547)	0
Tax (Expense) or Benefit:
Foreign currency translation	0	0	0	0
Net-of-Tax Amount:
Foreign currency translation	$ (71,231)	$ 0	$ (57,547)	$ 0