Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Description of the Business and Significant Accounting Policies (Goodwill) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Mar. 01, 2019	Dec. 31, 2018
Goodwill
Goodwill	$ 540,913		$ 429,645
OmniSource
Goodwill
Goodwill decrease due to tax benefit related to the normal amortization of the component	2,500
Steel Operations
Goodwill
Goodwill	359,283		245,473
Steel Operations \| United Steel Supply, LLC
Goodwill
Goodwill		$ 113,800
Metals Recycling Operations
Goodwill
Goodwill	179,705		182,247
Steel Fabrication Operations
Goodwill
Goodwill	$ 1,925		$ 1,925