Stock Incentive Plan Summary of Stock Option Activity (Details) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning of year	176,625	228,140	239,532
Granted	0	0	0
Exercised	(39,373)	(44,763)	(11,392)
Forfeited or expired	(8,502)	(6,752)	0
Outstanding, end of year	128,750	176,625	228,140
Options, Exercisable, Number	128,750	170,000	207,265
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding Options, Weighted Average Exercise Price, Beginning of Year	$ 24.88	$ 23.09	$ 22.50
Options, Grants in Period, Weighted Average Exercise Price	$ 0	$ 0.00	$ 0.00
Options, Exercises in Period, Weighted Average Exercise Price	$ 20.67	$ 15.90	$ 10.67
Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 24.34	$ 24.00	$ 0.00
Outstanding Options, Weighted Average Exercise Price, End of Year	$ 26.20	$ 24.88	$ 23.09
Options, Exercisable, Weighted Average Exercise Price	$ 26.20	$ 24.95	$ 22.98
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options, Outstanding, Weighted Average Remaining Contractual Term	2 years 5 months 1 day	2 years 9 months 22 days	3 years 3 months 26 days
Options, Exercisable, Weighted Average Remaining Contractual Term	2 years 5 months 9 days	2 years 8 months 9 days	2 years 11 months 27 days
Options, Outstanding, Intrinsic Value	$ 0	$ 89,061	$ 159,552
Options, Exercisable, Intrinsic Value	0	89,061	159,552
Options, Exercises in Period, Total Intrinsic Value	$ 75,000	$ 332,000	$ 90,000
Antidilutive Outstanding and Exercisable option shares	128,750
Antidilutive Outstanding option shares		108,125	202,970
Antidilutive Exercisable option shares			182,095

Antidilutive stock option shares of common stock not considered in computing intrinsic value of Exercisable shares

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Antidilutive stock option shares of common stock not considered in computing intrinsic value of Outstanding and Exercisable shares

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Antidilutive stock option shares of common stock not considered in computing intrinsic value of Outstanding shares

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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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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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the 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 of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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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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