Derivatives and Fair Value of Financial Instruments (Details 3) (USD $)	Jun. 30, 2012 agreement	Dec. 31, 2011 agreement	Aug. 28, 2010 Y	May 29, 2010 Y agreement
Net commodity purchase contracts | Soybean oil
Derivative commodity instruments
Nonmonetary notional amount		2,580,000
Net commodity purchase contracts | Soybean meal
Derivative commodity instruments
Nonmonetary notional amount		23,300
Net commodity purchase contracts | Hogs
Derivative commodity instruments
Nonmonetary notional amount		2,280,000
Net commodity purchase contracts | Sugar
Derivative commodity instruments
Nonmonetary notional amount	14,243,000
Net commodity purchase contracts | Whey powder
Derivative commodity instruments
Nonmonetary notional amount	88,000
Net commodity sale contracts | Grain
Derivative commodity instruments
Nonmonetary notional amount	6,798,000	10,599,000
Net commodity sale contracts | Soybean oil
Derivative commodity instruments
Nonmonetary notional amount	5,580,000
Net commodity sale contracts | Soybean meal
Derivative commodity instruments
Nonmonetary notional amount	140,000
Net commodity sale contracts | Hogs
Derivative commodity instruments
Nonmonetary notional amount	3,680,000
Net commodity sale contracts | Heating oil
Derivative commodity instruments
Nonmonetary notional amount		1,176,000
Foreign currency exchange agreements
Derivative commodity instruments
Aggregate notional amount	$ 91,125,000	$ 158,266,000
Interest rate exchange agreements
Derivative commodity instruments
Aggregate notional amount	100,000,000	100,000,000
Notional amounts			$ 25,000,000	$ 25,000,000
Number of derivative agreements entered	4	4		3
Term of derivative contract (in years)			10	10