The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 44

-Subparagraph a(3)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

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- Definition

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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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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

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- Definition

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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-Publisher FASB

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-Paragraph 52

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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-Name Statement of Financial Accounting Standard (FAS)

-Number 141

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-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 98-1

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The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

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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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Completed Acquisitions Purchase Price Allocation (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012 Y	Jun. 30, 2012 Customer Relationships [Member] Y	Jun. 30, 2012 Product Technology [Member] Y	Jun. 30, 2012 Tradenames and other [Member] Y	May 01, 2012 Doe & Ingalls [Member]	May 01, 2012 Doe & Ingalls [Member] Customer Relationships [Member]	May 01, 2012 Doe & Ingalls [Member] Product Technology [Member]	May 01, 2012 Doe & Ingalls [Member] Tradenames and other [Member]
Net Assets Acquired
Current assets					$ 21.7
Property, plant and equipment					11.6
Intangible assets (Definite Lived)						68.2	1.1	16.8
Goodwill					81.3
Other assets					0.4
Liabilities assumed					(24.8)
Total Purchase Price					$ 176.3
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life (in years)	12	13	8	8