Stock-Based Compensation Plans (Schedule of Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Number of Shares
Options outstanding at January 1, 2013	139,400
Granted	1,000
Exercised	(22,100)
Forfeited and expired	(6,350)
Options outstanding at December 31, 2013	111,950
Options exercisable at December 31, 2013	77,000
Weighted Average Exercise Price Per Share
Options outstanding at January 1, 2013	$ 32.97
Granted	$ 41.11
Exercised	$ 31.24
Forfeited and expired	$ 33.23
Options outstanding at December 31, 2013	$ 33.36
Options exercisable at December 31, 2013	$ 34.06
Weighted- Average Remaining Contractual Term
Options outstanding at December 31, 2013	4 years 10 months 24 days
Options exercisable at December 31, 2013	4 years
Aggregate Intrinsic Value
Options outstanding at December 31, 2013	$ 987
Options exercisable at December 31, 2013	$ 637

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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