Condensed Consolidated Statements of Income (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement [Abstract]
Net sales	$ 812,171	$ 833,165	$ 1,586,423	$ 1,626,649
Cost of sales	693,346	727,607	1,372,497	1,432,578
Selling, general and administrative	62,484	65,131	116,261	132,940
Depreciation	13,455	12,833	27,082	26,057
Amortization	2,341	2,361	4,683	4,709
Equity in (earnings) losses of investees	(72)	866	(72)	2,569
Restructuring and relocation costs	41	6,770	258	10,633
Operating income	40,576	17,597	65,714	17,163
Interest income	775	750	1,507	1,649
Interest expense	(14,778)	(10,239)	(29,342)	(20,746)
Loss on debt extinguishment	0	0	(6,275)	0
Other income, net	1,568	0	2,123	0
Income (loss) before income taxes	28,141	8,108	33,727	(1,934)
Income tax (expense) benefit	2,959	(2,600)	(250)	(3,700)
Net income (loss)	$ 31,100	$ 5,508	$ 33,477	$ (5,634)
Earnings (loss) per common share - basic (in dollars per share)	$ 0.67	$ 0.12	$ 0.72	$ (0.12)
Earnings (loss) per common share - diluted (in dollars per share)	$ 0.66	$ 0.12	$ 0.71	$ (0.12)