Stock-Based Compensation (Details 4) (Restricted Stock and Restricted Stock Units, USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2011 Y	Sep. 30, 2010	Dec. 31, 2007 Y
Restricted Stock and Restricted Stock Units
Restricted Stock and Restricted Stock Unit Activity:
Number of Awards - Nonvested - Beginning balance	5,573,302
Number of Awards - Granted - Annual	889,448
Number of Awards - Granted - Performance shares	375,146
Number of Awards - Granted - Other	335,164
Number of Awards - Vested	(1,277,111)
Number of Awards - Forfeited	(106,367)
Number of Awards - Nonvested - Ending balance	5,789,582
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures
Weighted Average Grant Date Fair Value - Nonvested - Beginning balance	$ 70.43
Weighted Average Grant Date Fair Value - Annual	$ 89.46
Weighted Average Grant Date Fair Value - Performance Shares	$ 83.34
Weighted Average Grant Date Fair Value - Other	$ 87.55
Weighted Average Grant Date Fair Value - Vested	$ 72.33
Weighted Average Grant Date Fair Value - Forfeited	$ 71.58
Weighted Average Grant Date Fair Value - Nonvested - Ending balance	$ 74.74
Compensation expense yet to be recognized for restricted stock and restricted stock units	$ 121
Weighted average life for remaining vesting period of restricted stock and restricted stock units (in years)	2.0
Vesting period, generally (in years)	3
Vesting period of "buyout" grant of restricted stock units (in years)			5
Fair value of restricted stock and restricted stock units that vested	92	60
Tax benefit realized from vesting of restricted stock and restricted stock units	$ 42	$ 20

As of the latest balance-sheet date presented, the total compensation cost related to outstanding, nonvested share-based compensation awards other than options not yet recognized (will be charged against earnings as services are performed or other vesting criteria are met).

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Disclosure of the aggregate tax benefit realized from the vesting of restrictied stock and restricted stock units during the period.

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The weighted average period over which unrecognized share-based compensation costs on equity awards other than options are expected to be reported.

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Description of the period of time over which an employee's right to exercise an equity award other than options is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in years.

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The number of shares issuable under a share-based award plan pertaining to grants made during the period on other than stock option plans.

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The number of shares issuable under a share-based award plan pertaining to grants made during the period on performance shares.

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The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans, other than annual and performance shares.

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The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans, other than annual shares.

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The vesting period of "buyout" grant from restricted stock units issued associated with changes in the MSOP program.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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-Name Statement of Financial Accounting Standard (FAS)

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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