Segment Information (Details 3) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Operating income (loss)
Gross profit increase (decrease) from intra-company sales	$ 222,771,000	$ 147,692,000	$ 386,075,000	$ 323,956,000
Assets elimination
Elimination of intra-company receivables	910,796,000		910,796,000		720,600,000
Other	76,439,000		76,439,000		115,083,000
Total assets	5,985,202,000	5,735,910,000	5,985,202,000	5,735,910,000	5,933,006,000
Liabilities elimination
Elimination of intra-company payables	440,691,000		440,691,000		414,932,000
Liabilities	3,025,992,000	3,220,439,000	3,025,992,000	3,220,439,000
Intersegment Elimination [Member]
Operating income (loss)
Gross profit increase (decrease) from intra-company sales	(1,400,000)	3,000,000	2,800,000	4,700,000
Assets elimination
Elimination of intra-company receivables	(52,000,000)	(40,200,000)	(52,000,000)	(40,200,000)
Elimination of intra-company debt	(158,100,000)	(154,200,000)	(158,100,000)	(154,200,000)
Other	(10,700,000)	(7,800,000)	(10,700,000)	(7,800,000)
Total assets	(220,752,000)	(202,224,000)	(220,752,000)	(202,224,000)
Liabilities elimination
Elimination of intra-company payables	(52,400,000)	(40,500,000)	(52,400,000)	(40,500,000)
Elimination of intra-company debt	(158,100,000)	(154,200,000)	(158,100,000)	(154,200,000)
Other	700,000	1,300,000	700,000	1,300,000
Liabilities	$ (209,776,000)	$ (193,358,000)	$ (209,776,000)	$ (193,358,000)