Segment Information (Details 3) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Operating income (loss)
Gross profit increase (reduction) from intra-company sales	$ 197,192,000	$ 156,401,000	$ 521,148,000	$ 539,801,000
Assets elimination
Elimination of intra-company receivables	772,873,000		772,873,000		642,363,000
Other	120,742,000		120,742,000		132,816,000
Total assets	5,874,305,000	5,775,516,000	5,874,305,000	5,775,516,000	5,815,416,000
Liabilities elimination
Elimination of intra-company payables	426,406,000		426,406,000		360,097,000
Liabilities	3,316,517,000	3,342,688,000	3,316,517,000	3,342,688,000
Eliminations
Operating income (loss)
Gross profit increase (reduction) from intra-company sales	2,100,000	(3,900,000)	2,500,000	(5,100,000)
Assets elimination
Elimination of intra-company receivables	(46,900,000)	(35,800,000)	(46,900,000)	(35,800,000)
Elimination of intra-company debt	(153,600,000)	(129,100,000)	(153,600,000)	(129,100,000)
Other	(10,000,000)	(17,100,000)	(10,000,000)	(17,100,000)
Total assets	(210,502,000)	(181,953,000)	(210,502,000)	(181,953,000)
Liabilities elimination
Elimination of intra-company payables	(47,300,000)	(39,000,000)	(47,300,000)	(39,000,000)
Elimination of intra-company debt	(153,600,000)	(129,100,000)	(153,600,000)	(129,100,000)
Other liabilities	600,000	(2,100,000)	600,000	(2,100,000)
Liabilities	$ (200,304,000)	$ (170,206,000)	$ (200,304,000)	$ (170,206,000)