Stock-Based Compensation (Details 2) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award
Shares authorized under existing stock based compensation plans (in shares)	274,100,000
Additional shares considered authorized under previous stock based compensation plans (in shares)	66,200,000
Unused shares available for grant (in shares)	124,800,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of awards vested per year (as a percent)	25.00%
Vesting period (in years)	4 years
Contractual term (in years)	10 years
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share)	$ 94	$ 98	$ 102
Options exercised (in dollars per share)	$ 98	$ 101	$ 98
Options canceled/expired (in dollars per share)	$ 107	$ 108	$ 127
Outstanding, ending balance (in dollars per share)	$ 90	$ 94	$ 98
Exercisable at end of period (in dollars per share)	$ 90	$ 94	$ 98
Number of Shares under Option
Outstanding, beginning balance (in shares)	39,197,728	73,210,457	119,307,170
Options exercised (in shares)	(18,144,309)	(33,078,316)	(28,100,192)
Options canceled/expired (in shares)	(391,097)	(934,413)	(17,996,521)
Outstanding, ending balance (in shares)	20,662,322	39,197,728	73,210,457
Exercisable at end of period (in shares)	20,662,322	39,197,728	72,217,126
Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	1 year
Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	5 years

The contractual life of stock based compensation awards.

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The description of award terms as to how many shares or a portion of an award is no longer contingent on the satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

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The additional number of shares granted under previous share-based compensation plans which, when canceled, are authorized to be reissued under the current plan.

+ References

No definition available.

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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).

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

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

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of share options (or share units) exercised during the current period.

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