Consolidated Statements of Operations (USD $)
In Thousands, except Per Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Income Statement [Abstract]      
Net sales $ 5,127,961 $ 5,307,414 $ 5,451,909
Cost of sales 4,830,640 4,949,404 5,115,188
Gross profit 297,321 358,010 336,721
Selling, general and administrative expenses 232,586 216,858 182,069
Equity in earnings of unconsolidated affiliates 47,749 39,138 27,140
Operating income 112,484 180,290 181,792
Interest expense, net 124,923 132,038 109,971
Loss on extinguishment of long-term debt 7,390 20,744  
Other expense, net 27,784 27,877 23,979
Income (loss) before income taxes (47,613) (369) 47,842
Provision for income taxes 19,719 21,849 17,560
Net income (loss) $ (67,332) $ (22,218) $ 30,282
Weighted average shares- basic and diluted 43,476 37,270 16,123
Net income (loss) per share- basic and diluted $ (1.55) $ (0.60) $ 1.88