Business Segments (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Segment	Jun. 30, 2011	Dec. 31, 2011
Business Segments
Number of reportable segments			2
Business Segments
Net sales	$ 2,308,318,000	$ 1,447,716,000	$ 4,276,949,000	$ 2,614,981,000
Cost of product sold (exclusive of depreciation and amortization)	1,874,210,000	1,123,375,000	3,509,365,000	2,060,197,000
Direct operating expenses (exclusive of depreciation and amortization)	94,099,000	66,207,000	209,613,000	134,641,000
Insurance recovery - business interruption				(2,870,000)
Depreciation and amortization	32,190,000	22,043,000	64,302,000	44,054,000
Operating income (loss)	235,772,000	217,920,000	376,280,000	327,526,000
Capital expenditures	45,634,000	13,642,000	105,159,000	20,979,000
Total assets	3,284,714,000		3,284,714,000		3,119,291,000
Goodwill	40,969,000		40,969,000		40,969,000
Petroleum
Business Segments
Intercompany sales	2,400,000	3,500,000	4,800,000	4,900,000
Intercompany cost of product sold (exclusive of depreciation and amortization)	(100,000)	6,100,000	5,600,000	5,300,000
Net sales	2,229,539,000	1,376,681,000	4,128,024,000	2,487,941,000
Cost of product sold (exclusive of depreciation and amortization)	1,866,155,000	1,122,763,000	3,496,820,000	2,053,046,000
Direct operating expenses (exclusive of depreciation and amortization)	71,583,000	44,054,000	164,286,000	89,464,000
Depreciation and amortization	26,638,000	16,966,000	52,897,000	33,882,000
Operating income (loss)	248,856,000	183,537,000	383,752,000	289,227,000
Capital expenditures	26,990,000	8,626,000	62,393,000	13,214,000
Total assets	2,540,013,000		2,540,013,000		2,322,148,000
Nitrogen Fertilizer
Business Segments
Intercompany sales		6,100,000	5,700,000	6,100,000
Intercompany cost of product sold (exclusive of depreciation and amortization)	2,300,000	2,900,000	5,200,000	3,600,000
Cost of product sold related to the transfer of excess hydrogen	100,000		100,000	700,000
Net sales	81,431,000	80,673,000	159,707,000	138,050,000
Cost of product sold (exclusive of depreciation and amortization)	10,725,000	9,746,000	23,323,000	17,237,000
Direct operating expenses (exclusive of depreciation and amortization)	22,524,000	22,266,000	45,361,000	45,290,000
Insurance recovery - business interruption				(2,870,000)
Depreciation and amortization	5,158,000	4,648,000	10,596,000	9,285,000
Operating income (loss)	36,047,000	39,346,000	67,473,000	56,112,000
Capital expenditures	16,944,000	4,006,000	39,218,000	6,047,000
Total assets	639,703,000		639,703,000		659,309,000
Goodwill	40,969,000		40,969,000		40,969,000
Other
Business Segments
Direct operating expenses (exclusive of depreciation and amortization)	(8,000)	(113,000)	(34,000)	(113,000)
Depreciation and amortization	394,000	429,000	809,000	887,000
Operating income (loss)	(49,131,000)	(4,963,000)	(74,945,000)	(17,813,000)
Capital expenditures	1,700,000	1,010,000	3,548,000	1,718,000
Total assets	104,998,000		104,998,000		137,834,000
Intersegment elimination
Business Segments
Net sales	(2,652,000)	(9,638,000)	(10,782,000)	(11,010,000)
Cost of product sold (exclusive of depreciation and amortization)	$ (2,670,000)	$ (9,134,000)	$ (10,778,000)	$ (10,086,000)