Condensed Consolidated Statements of Operations (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Revenues	$ 2,995,136	$ 4,746,443
Costs and expenses:
Cost of sales, excluding depreciation	2,529,040	4,147,684
Operating expenses, excluding depreciation	233,377	268,899
General and administrative expenses	32,530	36,624
Gain on sale of assets	(359)	(186)
Depreciation and amortization expense	46,259	33,215
Total cost and expenses	2,840,847	4,486,236
Income from operations	154,289	260,207
Other income (expense)
Change in fair value of catalyst leases	2,039	(2,001)
Interest expense, net	(21,072)	(25,456)
Net income	$ 135,256	$ 232,750