Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012	Dec. 29, 2012
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 423,593	$ 436,674	$ 869,015	$ 823,782
Net income	26,418	36,225	58,823	64,796
Interest expense	(5,669)	(5,753)	(11,294)	(12,678)
Assets	1,641,825		1,641,825		1,552,416
Rendering [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	350,597	371,481	717,771	693,793
Net income	60,219	73,061	131,898	137,639
Assets	1,090,732		1,090,732		1,088,775
Bakery [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	72,996	65,193	151,244	129,989
Net income	13,743	13,093	28,183	24,145
Assets	170,188		170,188		170,566
Unallocated Amount to Segment [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net income	(41,875)	(44,176)	(89,964)	(84,310)
Interest expense	(5,669)	(5,753)	(11,294)	(12,678)
Assets	$ 380,905		$ 380,905		$ 293,075