Stock-Based Compensation (Summary of Stock Option Activity Under all Stock Plans) (Details) (USD $) In Millions, except Per Share data	6 Months Ended
Jun. 30, 2011
Stock-Based Compensation
Beginning balance, shares available for grant	1.4
Options authorized, shares available for grant	1.3
Options granted, shares available for grant	(1.2)
Ending balance, shares available for grant	1.5
Beginning balance, number of options outstanding	4.8
Options granted, number outstanding	1.2
Options exercised, number outstanding	(0.5)
Options forfeited/expired, number outstanding	(0.1)
Ending balance, number of options outstanding	5.4
Beginning balance, number of options outstanding, weighted average exercise price per share	$ 209.03
Options granted, weighted average exercise price per share	$ 339.76
Options exercised, weighted average exercise price per share	$ 142.81
Options forfeited/expired, weighted average exercise price per share	$ 274.47
Ending balance, number of options outstanding, weighted average exercise price per share	$ 244.66

The number of stock options authorized (by board of directors or stockholders) during the reporting period to be available for grant under the Company's stock option plans.

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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 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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The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that lapsed during the reporting period.

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Net number of share options (or share units) granted during the period.

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The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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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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The number of shares newly issued during the reporting period under the plan.

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

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