Common Stock (Schedule of Stock Option Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Equity and Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted Average Exercise Price	$ 19.99
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period	875	1,288	1,536
Granted	0	74	1,148
Exercised	(213)	(484)	(1,362)
Canceled	(10)	(3)	(34)
Outstanding at end of period	652	875	1,288
Exercisable	564	684	770
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period	$ 17.85	$ 13.69	$ 9.30
Granted	$ 0.00	$ 53.78	$ 22.17
Exercised	$ 11.21	$ 12.22	$ 15.42
Canceled	$ 19.98	$ 23.63	$ 32.26
Outstanding at end of period	$ 19.99	$ 17.85	$ 13.69
Exercisable	$ 16.18	$ 11.67	$ 10.97

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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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-Publisher FASB

-Name Accounting Standards Codification

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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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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.

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

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

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No definition available.

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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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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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