Pensions Healthcare Costs (Details) (USD $) In Millions	12 Months Ended
Dec. 31, 2010
Effect of One Percentage Point Change In Assumed Health Care Cost Trend Rates
Effect Of One Percentage Point Increase On Service And Interest Cost Components	$ 0.3
Effect Of One Percentage Point Decrease On Service And Interest Cost Components	(0.3)
Effect Of One Percentage Point Increase On Healthcare Benefit Obligation	4.5
Effect Of One Percentage Point Decrease On Healthcare Benefit Obligation	$ (3.5)

The effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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- Definition

The effect of a one-percentage- point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ Details

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- Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basis for the accounting.)

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basis for the accounting.)

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m

+ Details

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