Uncertain Tax Positions (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Uncertain Tax Positions
Unrecognized tax benefits	$ 31.8	$ 51.4
Increase in unrecognized tax benefit	2.6
Unrecognized tax benefits that would impact effective tax rate	15.0	31.6
Decrease in unrecognized tax benefit within 12 months	0.5
Unrecognized tax benefits, increase in income tax penalties and interest accrued	$ 0.2

Increase (decrease) in accrual for interest and penalties related to unrecognized tax benefits.

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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.

+ Details

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- Definition

Uncertain Tax Positions [Abstract]

+ Details

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- Definition

The gross amount of unrecognized tax benefits (tax reductions recognized in financial reports but excluded from tax returns) pertaining to uncertain tax positions taken in tax returns as of the beginning balance sheet date, excluding amounts pertaining to examined tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a

+ Details

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- Definition

The net amount of all increases and decreases in unrecognized tax benefits for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a

+ Details

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph b

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