Goodwill and Other Intangible Assets - Schedule of Change in Net Carrying Amount of Goodwill by Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			3 Months Ended
Apr. 05, 2014	Apr. 05, 2014 Steel Mills [Member]	Dec. 31, 2013 Steel Mills [Member]	Apr. 05, 2014 Steel Products [Member]	Apr. 05, 2014 Raw Materials [Member]	Dec. 31, 2013 Raw Materials [Member]
Goodwill [Line Items]
Balance, beginning of period	$ 1,973,608	$ 495,897	$ 495,897	$ 774,486	$ 703,225	$ 703,225
Translation	(14,641)			(14,641)
Balance, end of period	$ 1,958,967	$ 495,897	$ 495,897	$ 759,845	$ 703,225	$ 703,225

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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