Summary of Significant Accounting Policies (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2013 segment	Dec. 31, 2012	Dec. 31, 2011
Cost Classifications
Depreciation expense incurred related to the cost of product sold	$ 280,000,000	$ 100,000,000	$ 58,000,000
Depreciation and amortization not included in direct operating expenses	25,300,000	20,600,000	18,800,000
Depreciation and amortization not included in selling, general and administrative expenses	5,000	5,000	10,000
Segment Reporting
Number of operating segments	1
Revenue Recognition
Expected period of delivery of deferred revenue	12 months
Nitrogen fertilizer plant
Planned Major Maintenance Costs
Turnaround costs		$ 4,800,000
Minimum | Nitrogen fertilizer plant
Planned Major Maintenance Costs
Frequency of planned major maintenance activities	2 years
Maximum | Nitrogen fertilizer plant
Planned Major Maintenance Costs
Frequency of planned major maintenance activities	3 years