Commitments and Contingencies (Details) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended	12 Months Ended
	Oct. 31, 2009 USD ($)	Oct. 31, 2008 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2009 t	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies			$ 1,100		$ 1,100		$ 1,100
Document Period End Date					Jun. 30, 2015
Environmental [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies			1,100		$ 1,100
Civil Penalty [Domain]
Loss Contingencies [Line Items]
Estimated Litigation Liability			900		$ 900
Mexicana vs. Sudamfos Lawsuit [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value		$ 1,200
Phosphoric Acid | t						12,500
Loss Contingency, Damages Sought, Counter Lawsuit	$ 3,000
Louisiana sales and use tax [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value				$ 1,200
Minimum [Member] | Environmental [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Anticipated Cost			900
Maximum [Member] | Environmental [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Anticipated Cost			$ 1,300