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Percentage of FMV common stock options granted.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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The highest quantity of shares an employee can purchase under the plan per period.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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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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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended	0 Months Ended	1 Months Ended	3 Months Ended
Stock-Based Compensation (Details Textual) (USD $)	Mar. 31, 2015	Apr. 12, 2010	May 29, 2014	Mar. 31, 2014	Dec. 31, 2014
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	590,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	10,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,009,168				2,436,834
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 3.84
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 15,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	12,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	46,664
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	2,600,000
Director Stock Option Plan - 1999 [Member]
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,975,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2,514,798
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	807,782
Nineteen Ninety Nine Stock Incentive Plan [Member]
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2,892,500
Percent FMV Common Stock Options Granted	100.00%
Plan 2009 [Member]
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			5,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	1,506,248
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	230,420
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		2,000,000	1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee	1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,434,334
Plan 1999 Plan 2009 And Director Plan [Member]
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,009,168
Common Stock, Capital Shares Reserved for Future Issuance	1,361,070
Restricted Stock [Member]
Stock Based Compensation Details [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	1,200,000
Allocated Share-based Compensation Expense	$ 99,000			$ 183,300
Restricted Stock [Member] \| Plan 2009 [Member]
Stock Based Compensation Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	112,750