Goodwill and Other Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Change in Net Carrying Amount of Goodwill by Segment

The change in the net carrying amount of goodwill for the nine months ended September 30, 2017, by segment is as follows (in thousands):

	Steel Mills		Steel Products		Raw Materials		Total
Balance at December 31, 2016	$	620,156	$	702,995	$	729,577	$	2,052,728
Acquisitions		125,328		7,157		—		132,485
Translation		—		23,033		—		23,033
Balance at September 30, 2017	$	745,484	$	733,185	$	729,577	$	2,208,246

Schedule of Intangible Assets

Intangible assets with estimated useful lives of five to 22 years are amortized on a straight-line or accelerated basis and were comprised of the following as of September 30, 2017 and December 31, 2016 (in thousands):

	September 30, 2017				December 31, 2016
	Gross Amount		Accumulated Amortization		Gross Amount		Accumulated Amortization
Customer relationships	$	1,422,569	$	622,440	$	1,295,803	$	566,884
Trademarks and trade names		176,950		74,551		161,851		66,494
Other		62,807		25,030		62,807		20,248
	$	1,662,326	$	722,021	$	1,520,461	$	653,626