Acquisition (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Y	Jan. 14, 2011
Acquisition (Textual) [Abstract]
The total consideration for the acquisition		$ 143.3
Recorded goodwill in connection with acquisition		42.0
Recorded intangible assets in connection with acquisition		33.9
Amount of goodwill deductible for tax purposes		42.0
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets (Textual) [Abstract]
Customer Relationship		26.7
Minimum Life of intangible Asset	11
Maximum Life of intangible Asset	12
Other Intangibles [Member]
Acquired Finite-Lived Intangible Assets (Textual) [Abstract]
Customer Relationship		2.2
Minimum Life of intangible Asset	1
Maximum Life of intangible Asset	8
Trade Names [Member]
Acquired Indefinite Lived Intangible Assets (Textual) [Abstract]
Trade names		$ 5.0

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- Definition

Business acquisition purchase price allocation intangible assets.

+ References

No definition available.

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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.

+ References

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- Definition

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

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 51

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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.

+ References

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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 acquisition cost of a business combination allocated to an identifiable intangible asset that will not be amortized. Does not include goodwill.

+ References

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The maximum useful life of a major finite-lived intangible asset class. 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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