Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Revenues	$ 134,125	$ 139,579
Costs and expenses:
Cost of goods sold	107,772	98,593
Selling, general and administrative expenses	12,326	9,677
Total costs and expenses	120,098	108,270
Operating income	14,027	31,309
Interest expense, net	(8,069)	(5,460)
Income before income taxes	5,958	25,849
Income taxes	(302)	(5,499)
Net income	$ 5,656	$ 20,350
Net income per share:
Basic (in dollars per share)	$ 0.14	$ 0.50
Diluted (in dollars per share)	$ 0.14	$ 0.50
Distributions per share (in dollars per share)	$ 0.375	$ 0.35
Weighted average shares outstanding (in thousands):
Basic (in shares)	40,801,993	40,561,017
Diluted (in shares)	40,885,116	40,682,108