Stock-Based Compensation (Option Activity) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Stock-Based Compensation [Abstract]
Options Outstanding, Number, Beginning Balance	662,048	553,248
Options, Grants in Period, Gross	191,685	176,710
Options, Exercises in Period	(6,610)	(11,498)
Options, Forfeitures and Expirations in Period	(52,145)	(56,412)
Options Outstanding, Number, Ending Balance	794,978	662,048
Options Exercisable, Number	492,468	418,858
Options Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 23.46	$ 23.79
Options, Grants in Period, Weighted-Average Exercise Price	$ 25.55	$ 22.75
Options, Exercises in Period, Weighted-Average Exercise Price	$ 22.90	$ 16.82
Options, Forfeitures and Expirations in Period, Weighted-Average Exercise Price	$ 25.11	$ 25.76
Options Outstanding, Weighted Average Exercise Price, Ending Balance	$ 19.41	$ 23.46
Options Exercisable, Weighted Average Exercise Price	$ 23.58	$ 23.49

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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

-Topic 718

-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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- Definition

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

+ References

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

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