Income Per Share of Common Stock (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Per Share of Common Stock
Net income for basic and diluted income per common share	$ 2,365	$ 4,492
Weighted-average shares for basic income per common share	5,597,000	5,576,000
Effect of dilutive securities:
Employee and director stock options (in shares)	8,000	10,000
Adjusted weighted-average shares and assumed exercises for diluted income per common share	5,605,000	5,586,000
Basic net income per common share (in dollars per share)	$ 0.42us-gaap_EarningsPerShareBasic	$ 0.81us-gaap_EarningsPerShareBasic
Diluted net income per common share (in dollars per share)	$ 0.42us-gaap_EarningsPerShareDiluted	$ 0.80us-gaap_EarningsPerShareDiluted
Options
Anti-dilutive securities
Anti-dilutive shares of common stock excluded from the calculation of dilutive securities	17,000	15,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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