Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Oct. 01, 2011	Oct. 02, 2010	Oct. 01, 2011 time	Oct. 02, 2010
Income Taxes
Effective income tax rates (as a percent)	32.20%	37.40%	33.40%	35.60%
Number of times of reversal of tax reserves			1
Reasonably possible potential reduction in unrecognized tax benefits over the next twelve months	$ 2.0		$ 2.0
Liability for uncertain tax positions	$ 10.1		$ 10.1

Represents the number of times, the reversal of tax reserves took place resulting in a fluctuation in income tax rates.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(h)(2))

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 6, 7, 8

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

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- Definition

The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)

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