Employee Benefits (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Plans had an ABO in excess of plan assets
ABO	$ 1,200	$ 1,200
Weighted-average rates to determine the actuarial present value of benefit obligations
Discount rate	4.00%	4.75%
Weighted-average rates to determine net pension cost
Discount rate	4.75%	5.25%	5.75%
Compensation increase rate			4.00%
Expected return on plan assets	7.75%	8.25%	8.25%
Asset target allocations prescribed by the pension funds' investment policies
Equity securities	46.00%
Fixed income securities	28.00%
Convertible securities	5.00%
Other assets	21.00%
Total	100.00%
Pension Plans, Defined Benefit [Member]
Changes in the FVA
FVA at beginning of year	914	839
Actual return on plan assets	(29)	96
Employer contributions	121	70
Benefit payments	(88)	(91)
FVA at end of year	918	914
Funded status of the pension plans recognized in the balance sheets
Funded Status	(310)	(336)
Net prepaid pension cost recognized consists of:
Current liabilities	(14)	(14)
Noncurrent liabilities	(296)	(322)
Net prepaid pension cost recognized	(310)	(336)
Plans had an ABO in excess of plan assets
PBO	1,228	1,250
ABO	1,225	1,248
Fair value of plan assets	$ 918	$ 914
Weighted-average rates to determine the actuarial present value of benefit obligations
Discount rate	4.00%	4.75%
Compensation increase rate

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Defined benefit plans net prepaid pension cost recognized.

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Defined benefit plan target allocation percentage of assets total.

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Defined benefit plan target allocation percentage of assets convertible securities.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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

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Expected rate of compensation increases (for pay-related plans).

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

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

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Expected rate of compensation increases (for pay-related plans).

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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The amount of contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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- Definition

Target allocation percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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Target allocation percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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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.

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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.

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