Goodwill and Intangible Assets (Changes in goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011
Goodwill [Roll Forward]
Goodwill at beginning of period	$ 54,387	$ 12,545		$ 10,141
Acquisitions	4,167	41,842		1,690
Other adjustments				714
Goodwill at end of period	58,554	54,387		12,545
Grain
Goodwill [Roll Forward]
Goodwill at beginning of period	38,165	4,990		4,207
Acquisitions	0	33,175	[1]	0
Other adjustments				783
Goodwill at end of period	38,165	38,165		4,990
Plant Nutrient
Goodwill [Roll Forward]
Goodwill at beginning of period	13,550	6,869		5,248
Acquisitions	0	6,681		1,690
Other adjustments				(69)
Goodwill at end of period	13,550	13,550		6,869
Rail
Goodwill [Roll Forward]
Goodwill at beginning of period	0	0		0
Acquisitions	4,167	0		0
Other adjustments				0
Goodwill at end of period	4,167	0		0
Turf & Specialty
Goodwill [Roll Forward]
Goodwill at beginning of period	2,672	686		686
Acquisitions	0	1,986		0
Other adjustments				0
Goodwill at end of period	$ 2,672	$ 2,672		$ 686

[1] (a) The Grain acquisition balance has been revised to include the effect of the adjustments to the purchase price allocation in 2013. Discussed in Note 12. Business Acquisitions