Stock Based Compensation (Narrative) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price	$ 318.45
Grant date fair value	$ 82.03
Stock-based compensation expense	$ 15,655	$ 20,760
Stock-based compensation expense, net of tax	9,534	12,659
Stock only stock appreciation rights (SOSARs) granted	662
Options or SOSARs exercised	54
Options and SOSARs forfeited	22
Performance SOSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock only stock appreciation rights (SOSARs) granted	191
Leasehold Improvements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation recognized as capitalized development	$ 268	$ 520
First Half Vested [Member] \| Stock Options And SOSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for SOSARs	2 years
Second Half Vested [Member] \| Stock Options And SOSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for SOSARs	3 years

Vesting Period For Share Based Compensation Arrangement By Share Based Payment Award

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

+ References

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

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

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- Definition

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.

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

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

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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

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