Stock Incentive Plan Summary of Stock Option Activity (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning of year	128,750	176,625	228,140
Granted	0	0	0
Exercised	0	(39,373)	(44,763)
Forfeited or expired	76,750	8,502	6,752
Outstanding, end of year	52,000	128,750	176,625
Options, Exercisable, Number	52,000	128,750	170,000
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	$ 26.20	$ 24.88	$ 23.09
Options, Grants in Period, Weighted Average Exercise Price	$ 0	$ 0.00	$ 0.00
Options, Exercises in Period, Weighted Average Exercise Price	$ 0.00	$ 20.67	$ 15.90
Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 27.25	$ 24.34	$ 24.00
Outstanding Options, Weighted Average Exercise Price, End of Year	$ 24.64	$ 26.20	$ 24.88
Options, Exercisable, Weighted Average Exercise Price	$ 24.64	$ 26.20	$ 24.95
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options, Outstanding, Weighted Average Remaining Contractual Term	3 years 157 days	2 years 153 days	2 years 296 days
Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 157 days	2 years 153 days	2 years 252 days
Options, Outstanding, Intrinsic Value	$ 0	$ 0	$ 89,061
Options, Exercisable, Intrinsic Value	0	0	89,061
Options, Exercises in Period, Total Intrinsic Value		$ 75,000	$ 332,000
Antidilutive Outstanding and Exercisable option shares	52,000
Antidilutive Outstanding option shares		128,750
Antidilutive Exercisable option shares			108,125

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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-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.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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