Segment Information - Other Footnote (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Operating income (loss)
Corporate SG & A	$ (102,933)	$ (87,530)
Profit sharing	(27,231)	(9,291)
Operating income (loss)	334,566	131,965
Assets
Cash and equivalents	966,826	976,951	$ 841,483	$ 727,032
Accounts receivable	883,147		729,784
Inventories	1,361,550		1,275,211
Property, plant and equipment, net	2,760,544		2,787,215
Other	30,233		29,514
Total assets	6,704,035		$ 6,423,732
Other
Operating income (loss)
Corporate SG & A	(12,400)	(11,100)
Company-wide equity-based compensation	(9,600)	(7,000)
Profit sharing	(26,500)	(8,200)
Other, net	(5,500)	(5,600)
Operating income (loss)	(53,970)	(31,930)
Assets
Cash and equivalents	947,000
Accounts receivable	7,900
Inventories	28,700
Property, plant and equipment, net	166,200
Intra-company debt	15,100
Other	37,800
Total assets	1,202,678
Metals Recycling Operations
Operating income (loss)
Operating income (loss)	17,849	$ 2,767
Assets
Total assets	$ 1,010,993