Stock Based Compensation (Details) (Stock Options [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock Options [Member]
Number of options:
Number of Options outstanding, beginning	38,625	40,725	46,656
Number of Options granted
Number of Options exercised	14,550	2,100	2,625
Options forfeited or expired	3,825		3,306
Number of Options outstanding, ending	20,250	38,625	40,725
Number of Options exercisable	20,250	38,625	40,725
Weighted Average Exercise Price of Options outstanding, beginning	$ 17.29	$ 16.99	$ 16.62
Weighted Average Exercise Price of Options granted
Weighted Average Exercise Price of Options exercised	$ 18.87	$ 13.70	$ 13.70
Weighted Average Exercise Price of Options forfeited or expired	$ 18.51		$ 13.04
Weighted Average Exercise Price of Options outstanding, ending	$ 16.65	$ 17.29	$ 16.99
Weighted Average Exercise Price of Options exercisable	$ 16.65	$ 17.29	$ 16.99

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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.

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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.

+ References

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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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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

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