Retirement Benefits (Details 5) (USD $) In Millions	Dec. 31, 2010	Dec. 31, 2009
Amounts Recognized in the Consolidated Statements of Financial Position [Abstract]
Non-current assets	$ 320	$ 184
Non-current liability	(3,089)	(3,847)
Pension Benefits
Amounts Recognized in the Consolidated Statements of Financial Position [Abstract]
Non-current assets	275	148
Current liability	(94)	(45)
Non-current liability	(1,920)	(2,580)
Medical and Life Benefits
Amounts Recognized in the Consolidated Statements of Financial Position [Abstract]
Non-current assets	45	36
Current liability	(48)	(30)
Non-current liability	$ (1,169)	$ (1,267)

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The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

+ References

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

+ Details

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- Definition

For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

+ References

+ Details

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- Definition

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 3

+ Details

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