Compensation expense.

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- Definition

Disclosure of the aggregate tax benefit realized from the issuance of stock awards.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Forfeitures Percentage Objective Not Met.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Grants Percentage Financial Metric Met Exceeded.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage.

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- Definition

The period of time a share-based award, for executives, is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

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- Definition

The period of time a share-based award, for non-executives, is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

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- Definition

Share-based compensation expense included in discontinued operations.

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- Definition

The fair value, at the time of grant, for shares expected to be issued in the next fiscal year as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

+ Details

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- Definition

Number of shares expected to be issued in the next fiscal year as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

The fair value, at the time of grant, for shares issued during the reporting period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

The fair value, at the time of issuance, of shares issued during the reporting period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

Stock Option And Awards Plans.

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- Definition

Represents the expense recognized during the period arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-Subparagraph b

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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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
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

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

+ Details

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- Definition

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

+ References

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

+ Details

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- Definition

The weighted average period over which unrecognized share-based compensation costs are expected to be reported.

+ References

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

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- Definition

Reflects the dating as to when the share-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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

+ Details

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- Definition

Description of the estimated period of time over which an employee is required to provide service in exchange for the share-based payment award, which often is the vesting period. This period may be explicit or implicit based on the terms of the award, and may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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

+ Details

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- Definition

Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

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

+ Details

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- Definition

The maximum number of shares originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the share-based compensation plan. As stock options and equity instruments other than options are awarded to participants, the shares remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

+ Details

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- Definition

The difference between the maximum number of shares authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares already issued upon exercise of options or other share-based awards under the plan, and 2) shares reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ Details

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under 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 c(2)

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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(1)

+ Details

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- Definition

Number of shares issued during the period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 5

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Stock Compensation Plans (Details 4) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	$ 134	$ 101	$ 111
Unrecognized compensation expense related to unvested awards	172
Weighted-average period for unrecognized compensation expense to be charged to expense (years)	1.4
Stock-based compensation expense included in discontinued operations	16	11	13
Stock Option And Awards Plans [Abstract]
Common stock expected to be issued in 2011 to employees in settlement of prior year stock awards that were fully vested	1,300,000
Fair value of common stock expected to be issued in 2011 - grant date	101
Stock Option Plan [Member]
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	27	20	15
Tax benefits recognized in the condensed consolidated statements of operations for stock-based compensation	53	40	44
Realized tax benefits from exercise of stock options	17
Unrecognized compensation expense related to unvested awards	19
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 to 4 years
Expected option life for executives (years)	6
Expected option life for non-executives (years)	5
Weighted-average grant date fair value of stock options granted	$ 11	$ 7	$ 15
Total intrinsic value of options exercised	42	11	66
Available for future grant	7,257,000
Stock Awards Plan [Member]
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	107	81	96
Realized tax benefits from issuance of stock awards	34
Unrecognized compensation expense related to unvested awards	153
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 to 5 years
Fair value of common stock issued - grant date	91	161	155
Fair value of common stock issued - issuance date	$ 76	$ 111	$ 233
Common stock issued to employees in settlement of prior year stock awards that were fully vested	1,300,000	2,500,000	2,900,000
Restricted Share Plan [Member]
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 years
Maximum percentage of original grant that can be earned if financial metrics are met or exceeded	150.00%
Restricted Share Plan [Member] \| Corporate Policy Council [Member]
Stock Option And Awards Plans [Abstract]
Restricted stock forfeiture percentage if objectives are not met	100.00%
Maximum percentage of original grant that can be earned if financial metrics are met or exceeded	200.00%
Restricted Share Plan [Member] \| Eight Highest Paid Employees [Member]
Stock Option And Awards Plans [Abstract]
Restricted stock forfeiture percentage if objectives are not met	100.00%
Restricted Share Plan [Member] \| Other Employees [Member]
Stock Option And Awards Plans [Abstract]
Restricted stock forfeiture percentage if objectives are not met	70.00%
Stock Option Plan Granted Prior To 2008 [Member]
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	4 years
Stock option vesting percentage per year	25.00%
Stock option grant expiration period	10
Stock Option Plan Granted After 2008 [Member]
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 years
Stock option vesting percentage per year	33.00%
Stock option grant expiration period	7
Employee Plans [Member]
Stock Option And Awards Plans [Abstract]
Approved for grant under 2001 LTISP	50,000,000
Available for future grant	9,400,000
Non-Employee Plans [Member]
Stock Option And Awards Plans [Abstract]
Stock option grant expiration period	10
Available for future grant	93,000
Required service period under 1993 SPND (years)	5