Stock-Based Compensation (Detail 4) (Restricted Stock and Restricted Stock Units, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2010 years	Dec. 31, 2009	Dec. 31, 2008
Restricted Stock and Restricted Stock Units
Restricted Stock and Restricted Stock Unit Activity:
Number of Awards - Nonvested - Beginning balance	4,379,480	2,957,538	2,001,581
Number of Awards - Granted - Annual	902,549	1,150,819	924,120
Number of Awards - Granted - Performance shares	760,645
Number of Awards - Granted - Other	527,823	522,581	188,473
Number of Awards - Vested	(948,233)	(157,104)	(64,806)
Number of Awards - Forfeited	(48,962)	(94,354)	(91,830)
Number of Awards - Nonvested - Ending balance	5,573,302	4,379,480	2,957,538
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	$ 68.85	$ 77.41	$ 77.63
Weighted Average Grant Date Fair Value - Annual	$ 78.81	$ 53.89	$ 77.23
Weighted Average Grant Date Fair Value - Performance Shares	$ 73.99
Weighted Average Grant Date Fair Value - Other	$ 79.56	$ 54.82	$ 73.16
Weighted Average Grant Date Fair Value - Vested	$ 79.12	$ 73.26	$ 68.72
Weighted Average Grant Date Fair Value - Forfeited	$ 69.57	$ 69.57	$ 77.76
Weighted Average Grant Date Fair Value - Nonvested - Ending balance	$ 70.43	$ 68.85	$ 77.41
Compensation expense yet to be recognized for restricted stock and restricted stock units	$ 101
Weighted average life for remaining vesting period of restricted stock and restricted stock units (in years)	1.8
Fair value of restricted stock and stock units that vested	75	10	4
Tax benefit realized for tax deductions related to vesting of restricted stock and restricted stock units	$ 20
Vesting period, generally (in years)	3
Vesting period, 2007 one-time "buyout" (in years)	5

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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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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Under the 2007 buyout, 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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- Definition

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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- Definition

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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- Definition

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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- Definition

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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- Definition

The total recognized tax benefit related to compensation cost for share-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)

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The number of shares under a share-based award plan other than a stock option plan that were settled during the reporting period due to a failure to satisfy vesting conditions pertaining to all option plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(e)

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- Definition

The weighted average fair value as of the grant date of share-based award plans other than stock 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(e)

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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 (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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The number of outstanding awards on nonstock option plans (for example, phantom stock plan, stock 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(a)

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(b)

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on share-based plans excluding option plans (for example, phantom stock plan, stock 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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(a)

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(b)

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- Definition

The decrease in the number of shares potentially issuable under a share-based award plan pertaining to awards for which the grantee has gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(d)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(2)

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- Definition

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

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(d)

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