Business Acquisition (Details) (USD $) In Thousands, unless otherwise specified	Jul. 23, 2013 General Aluminum Forgings, LLC [Member]	Oct. 28, 2011 Forge Acquisition LLC [Member]
Assets acquired:
Accounts receivable	$ 645	$ 3,703
Inventory	1,173	3,961
Property and equipment	1,369	4,965
Intangible assets	1,100	9,000
Goodwill	605	3,522
Other	27	153
Total assets acquired	4,919	25,304
Liabilities assumed:
Accounts payable and accrued liabilities	532	418
Total purchase price	$ 4,387	$ 24,886

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The amount of acquisition cost of a business combination allocated to assets acquired.

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

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The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

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The amount of acquisition cost of a business combination allocated to receivables.

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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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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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