The average number of years of future service from employees over which the excess net actuarial gains or losses are amortized to expense.

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- Definition

The net actuarial (gain) loss included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost, net of tax.

+ Details

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- Definition

Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year.

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- Definition

Number of days notice required to redeem an investment.

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- Definition

Amount of unfunded commitments as of the balance sheet date.

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- Definition

The number of unfunded plans merged during the period. Unfunded plans may include foreign pension plans, which may not be funded because there are no tax advantages to funding plans in those jurisdictions, and may also include other postretirement benefit plans.

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- Definition

The US GAAP specified percentage of the greater of plan assets or projected benefit obligations by benefit plan over which the net actuarial gain or loss are subject to amortization to expense.

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- Definition

The maximum percentage of compensation the employer will contribute in order to match an employee's contribution to the plan.

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- Definition

The percentage of current retirees participating in postretirement medical benefit plans.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

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- Definition

The amount of contributions made by the employer.

+ References

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

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- Definition

Description of diversification use that is pertinent to an understanding of the plan investment policies and strategies.

+ References

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

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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

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- Definition

Narrative that provides an understanding of significant concentrations of risk within plan assets.

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

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- Definition

Descriptions and additional disclosures particular to unfunded plans. Unfunded plans may include foreign pension plans, which may not be funded because there are no tax advantages to funding plans in those jurisdictions, and may also include other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph B24

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 11

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Retirement Benefits (Details 14) (USD $)	12 Months Ended
Retirement Benefits (Details 14) (USD $)	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Medical and Life Benefit Plans Disclosure (Amounts in paragraphs)
Percentage current retirees participating in plans	50.00%
Expected Employer Contributions (Amounts in paragraphs)
Average future service period of employees	10
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Defined contribution plans cost	$ 288,000,000	$ 291,000,000	$ 262,000,000
Maximum percentage of employee compensation eligible for cash matching of employee contributions	4.00%
Pension Benefit Plans (Amounts in paragraphs)
Number of domestic unfunded non-qualified plans for directors, officers and certain employees	11
Accumulated benefit obligation for all defined benefit pension plans	20,500,000,000	19,300,000,000
Domestic unfunded non-qualified plans merged during period	9
Percentage threshold for excess gains or losses that are subject to amortization	10.00%
Information About Plan Assets (Amounts in paragraphs)
Maximum percentage of funds permitted to be invested in each trust account	no more than 5 percent
Number of real estate and private equity partnerships	167
Unfunded commitments	1,200,000,000	1,100,000,000
Notice period for alternative investments redemptions, days	90
Pension Benefits
Expected Employer Contributions (Amounts in paragraphs)
Employer contributions	789,000,000	657,000,000
Net after-tax actuarial loss	2,771,000,000	3,082,000,000
Average future service period of employees	10
Pension Benefits \| Employer Contributions - Required
Expected Employer Contributions (Amounts in paragraphs)
Expected employer contributions	59,000,000
Pension Benefits \| Employer Contributions - Discretionary
Expected Employer Contributions (Amounts in paragraphs)
Expected employer contributions	500,000,000
Employer contributions	728,000,000	601,000,000
Medical and Life Benefits
Expected Employer Contributions (Amounts in paragraphs)
Employer contributions	105,000,000	129,000,000
Medical and Life Benefits \| Employer Contributions - Required
Expected Employer Contributions (Amounts in paragraphs)
Expected employer contributions	$ 124,000,000