Acquisitions and Dispositions (Details Textual) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
Feb. 06, 2012 Y	Dec. 31, 2011 Business
Acquisitions and Dispositions (Textual)
Aggregate purchase price of acquisition	$ 205	$ 18
Amount of goodwill recognized	139	19
Goodwill deductible for income tax purposes	72	14
Identifiable intangible assets recognized	$ 32
Weighted average useful life for identifiable intangible assets, years	10
Number of businesses acquired		2

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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.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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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.

+ References

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-Publisher FASB

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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.

+ References

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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