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Acquisitions (Narrative) (Details) (USD $)	2 Months Ended	12 Months Ended
	Dec. 31, 2012 item	Dec. 31, 2013 item	Dec. 31, 2012 item	Dec. 31, 2011 item	Sep. 30, 2013	Nov. 30, 2012 Award Metals [Member]	Dec. 31, 2011 Award Metals [Member]	Jun. 03, 2011 Award Metals [Member]	Apr. 01, 2011 D.S. Brown [Member]	Jun. 03, 2011 Award Metals And DS Brown [Member]	Dec. 31, 2013 Purchased Assets of Four Businesses [Member]
Business Acquisition [Line Items]
Number of businesses acquired	3	1	4	2
Number of key markets			4
Aggregate purchase consideration for the acquisition	$ 43,263,000	$ 7,454,000	$ 43,263,000		$ 7,454,000			$ 13,369,000	$ 97,643,000		$ 146,000
Payment for aggregate purchase consideration	2,705,000	1,864,000	2,705,000		2,322,000	1,954,000	1,826,000
Excess consideration recorded as goodwill	15,263,000	2,466,000	15,263,000					4,328,000	46,198,000	50,526,000
Goodwill deductible for tax purposes										5,241,000
Legal and consulting fees		202,000	456,000	986,000
Additional cost of sales		$ 685,000	$ 244,000	$ 2,467,000
Award Metals facilities operated in U.S.		4

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Fair Value of the liabilities incurred by the acquirer to former owners of the acquiree, including the fair value of any contingent consideration. If liabilities transferred as consideration remain within the combined entity after the business combination (for example, because the assets or liabilities were transferred to the acquiree rather than to its former owners), and the acquirer therefore retains control of them; in that situation, the acquirer measures those liabilities at their carrying amounts immediately before the acquisition date.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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