Stock Based Compensation - Summary of Stock Options Outstanding (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of stock options outanding, Beginning of period	309,479	317,270
Number of stock options outanding, Granted		65,000
Number of stock options outanding, Exercised
Number of stock options outanding, Expired	(134,731)
Number of stock options outanding, Canceled or forfeited	(14,000)	(72,791)
Number of stock options outanding, End of period	160,748	309,479
Number of stock options outanding, Exercisable	115,333	226,980
Weighted average exercise price, Beginning of period	$ 19.75	$ 24.62
Weighted average exercise price, Granted		$ 2.86
Weighted average exercise price, Exercised
Weighted average exercise price, Expired	$ 12.07
Weighted average exercise price, Canceled or forfeited	$ 31.31	$ 25.90
Weighted average exercise price, End of period	$ 25.18	$ 19.75
Weighted average exercise price, Exercisable	$ 33.81	$ 25.57

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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.

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Gross 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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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