Inventories (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Inventory, Net [Abstract]
Grain	$ 598,729		$ 570,337
Ethanol and by-products (a)	22,927	[1]	5,461	[1]
Agricultural fertilizer and supplies	88,429		118,716
Lawn and garden fertilizer and corncob products	37,292		37,001
Retail merchandise	25,368		25,612
Railcar repair parts	3,764		3,063
Other	168		269
Total inventories	$ 776,677		$ 760,459

[1] Increase driven by the acquisition of TADE (see Note 12)