Derivatives (Details 2)	Sep. 30, 2011 Ton Gallon Bushel
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	523,927,000
Corn [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	288,009,000
Corn [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	112,170,000
Soybeans [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	30,819,000
Soybeans [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Wheat [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Wheat [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Oats [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Oats [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Soymeal [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Ethanol [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	156,364,000
Ethanol [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Other [Member] | Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Other [Member] | Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	0
Non-exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	339,467,000
Exchange traded [Member]
Commodity Derivative Contract Quantity Disclosure [Abstract]
Amount of quantities of price risk derivative instruments not designated as hedging instruments	31,129,000