Guarantees (Details)	9 Months Ended
	Sep. 30, 2015 USD ($) years
Guarantor Obligations [Line Items]
Agreement automatic renewal period (in years) | years	1
Contingent liability to SGX, amount of irrevocable letters of credit	$ 710,000,000
Family Farmer and Ranchers Protection Fund [Member]
Guarantor Obligations [Line Items]
Payment per participant	25,000
Payment per cooperative	100,000
FutureLosses	100,000,000
Payments under Guarantee	2,000,000
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 98,000,000