Average Investment Term, Alternative Investments

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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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No definition available.

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- Definition

Maximum percentage of funds permitted to be invested.

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No definition available.

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- Definition

Number of Real Estate and Private Equity Partnerships

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- Definition

Number of Unfunded Non-Qualified Pension and Postretirement Plans

+ References

No definition available.

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- Definition

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

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No definition available.

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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 Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

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- Definition

The interest rate used to adjust for the time value of money for the plan.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-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 715

-SubTopic 20

-Section 50

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-Subparagraph (k)(1)

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- Definition

Net increase or decrease in the plan benefit obligation during the reporting period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph a

-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

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

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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.

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Retirement Benefits (Details 13) (USD $)	12 Months Ended
Retirement Benefits (Details 13) (USD $)	Dec. 31, 2012 Unfunded-Non-qualified_Plans Real_Estate_and_Private_Equity_Partnerships	Dec. 31, 2011	Dec. 31, 2010
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Maximum percentage of employee compensation eligible for cash matching of employee contributions	4.00%
Defined contribution plans cost	$ 293,000,000	$ 297,000,000	$ 288,000,000
Medical and Life Benefit Plans Disclosure (Amounts in paragraphs)
Percentage current retirees participating in plans	55.00%
Information About Plan Assets (Amounts in paragraphs)
Accumulated net after-tax actuarial losses	5,100,000,000	3,900,000,000
Discount rate	4.12%	5.03%
Number of domestic unfunded non-qualified pension and postretirement plans	11
Accumulated benefit obligation for all defined benefit pension plans	27,200,000,000	23,600,000,000
Maximum percentage of funds permitted to be invested in trust accounts		5.00%
Number of real estate and private equity partnerships	164
Unfunded commitments	810,000,000	882,000,000
Average investment term, alternative investments	10 years
Notice period for alternative investments redemptions, days	90 days
Employer contributions	300,000,000	1,000,000,000
Pension Benefits
Information About Plan Assets (Amounts in paragraphs)
Reduction in Projected benefit obligation		640,000,000
Employer contributions	366,000,000	1,084,000,000
Pension Benefits \| Forecast
Information About Plan Assets (Amounts in paragraphs)
Expected 2013 employer contributions	500,000,000
Pension Benefits \| Employer Contributions - Required \| Forecast
Information About Plan Assets (Amounts in paragraphs)
Expected 2013 employer contributions	66,000,000
Medical and Life Benefits
Information About Plan Assets (Amounts in paragraphs)
Employer contributions	129,000,000	111,000,000
Medical and Life Benefits \| Employer Contributions - Required \| Forecast
Information About Plan Assets (Amounts in paragraphs)
Expected 2013 employer contributions	$ 110,000,000