Stock-Based Compensation (Summary of Stock Option Activity) (Details) (USD $)	3 Months Ended
Mar. 31, 2014
Stock-Based Compensation [Abstract]
Stock options, Outstanding at December 31, 2013, Number of options	3,312,693
Stock options, Granted, Number of options
Stock options, Exercised, Number of options	(177,504)
Stock options, Forfeited or expired, Number of options	(50,031)
Stock options, Outstanding at March 31, 2014, Number of options	3,085,158
Stock options, Outstanding at December 31, 2013, Weighted average exercise price	$ 35.70
Stock options, Granted, Weighted average exercise price
Stock options, Exercised, Weighted average exercise price	$ 32.91
Stock options, Forfeited or expired, Weighted average exercise price	$ 38.83
Stock options, Outstanding at March 31, 2014, Weighted average exercise price	$ 35.81
Stock options, Exercisable at March 31, 2014	1,927,252
Stock options Exercisable at March 31, 2014, Weighted average exercise price	$ 35.13

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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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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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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 vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

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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Weighted average price of options that were either forfeited or expired.

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

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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

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