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Amount of increase to additional paid-in capital (APIC) resulting from recognition of equity-based compensation for restricted stock units.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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Exercise price per share or per unit of warrants or rights outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Date the equity-based award expires, in CCYY-MM-DD format.

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No definition available.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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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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Net 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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

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No definition available.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Stock Based Compensation (Details) - USD ($)	3 Months Ended		12 Months Ended
Stock Based Compensation (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2018
Employees [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Unrecognized compensation expense related to unvested stock options, granted					$ 1,300,000
Unrecognized compensation cost, recognized as expense over a weighted-average period	1 year 14 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, shares subject to stock options (in shares)	2,865,512		2,865,512		2,772,755
Number of warrants issued (in shares)		0			1,667
Exercise price of warrants (in dollars per share)		$ 1.89
Share based compensation expense		$ 0
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate	2.42%	0.00%
Expected volatility	91.60%	0.00%
Expected lives	6 years	0 years
Expected dividend yield	0.00%	0.00%
Contractual term	10 years
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding at beginning of period (in shares)	2,865,512
Granted (in shares)	1,667
Forfeited or expired (in shares)	(94,424)
Outstanding at end of period (in shares)	2,772,755		2,865,512
Options exercisable at end of period (in shares)	2,151,186
Weighted-Average Exercise Price Options [Abstract]
Outstanding at beginning of period (in dollars per share)	$ 10.62
Granted (in dollars per share)	1.89
Forfeited or expired (in dollars per share)	3.20
Outstanding at end of period (in dollars per share)	10.86		$ 10.62
Options exercisable at end of period (in dollars per share)	$ 12.96
Stock Options [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, shares subject to stock options (in shares)	2,492,179		2,492,179		2,399,422
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding at beginning of period (in shares)	2,492,179
Granted (in shares)	1,667
Forfeited or expired (in shares)	(94,424)
Outstanding at end of period (in shares)	2,399,422		2,492,179
Options exercisable at end of period (in shares)	1,777,853
Stock Options [Member] \| Non-Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, shares subject to stock options (in shares)	373,333		373,333		373,333
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding at beginning of period (in shares)	373,333
Granted (in shares)	0
Forfeited or expired (in shares)	0
Outstanding at end of period (in shares)	373,333		373,333
Options exercisable at end of period (in shares)	373,333
Restricted Stock [Member]
Restricted Stock [Abstract]
Restricted stock expense	$ 137,766	$ 82,117
2000 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration date	Aug. 06, 2010
Share-based compensation, shares subject to stock options (in shares)	44,371				44,371
Share-based compensation, shares available for future grant (in shares)					0
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding at end of period (in shares)	44,371
2008 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, shares subject to stock options (in shares)	2,700,000				2,700,000
Share-based compensation, outstanding stock options (in shares)					400,000
Common stock reserved for future issuance (in shares)					5,000,000
Share-based compensation, shares available for future grant (in shares)					1,300,000
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding at end of period (in shares)	2,700,000
2008 Stock Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, outstanding stock options (in shares)					800,000
2008 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Chairman and Chief Executive Officer [Member]
Restricted Stock [Abstract]
Share based compensation arranged by share based payment award restricted stock granted (in shares)			387,597	387,597
Vesting period			3 years	3 years
Share based compensation of fair value of the restricted stock on the grant			$ 679,000	$ 1,000,000