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Stockholders' Equity (Details Textual) - USD ($)	1 Months Ended					3 Months Ended		6 Months Ended	9 Months Ended
Stockholders' Equity (Details Textual) - USD ($)	Jul. 31, 2018	Jun. 30, 2018	May 31, 2018	Feb. 27, 2018	Aug. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Class of Stock [Line Items]
Common Stock, Shares Authorized						62,500,000			62,500,000
Preferred Stock, Shares Authorized						2,000,000			2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			108,108
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 1.85
Stock Option Plan Description									The Consultant Plan provides for quarterly increases in the available number of authorized shares equal to the lesser of 1% of any new shares issued by the Company during the quarter immediately prior to the adjustment date or such lesser amount as the Board of Directors shall determine.
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number						694,881			694,881		754,989
Stock Issued During Period, Shares, New Issues	5,213,543			12,900,000
General And Administrative Expense Related To Stock Grant								$ 50,000	$ 150,000
Proceeds From Issuance Or Sale Of Equity									$ 23,511,000	$ 8,667,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term									10 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price									$ 1.85
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value									$ 239,000
Allocated Share-based Compensation Expense						$ 15,000			43,000
Stock Granted, Value, Share-based Compensation, Gross	$ 11,700,000		$ 200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding						$ 0			$ 0
Shares Issued, Price Per Share	$ 2.25
Proceeds from Issuance of Private Placement	$ 11,600,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	478,854
Sale of Stock, Price Per Share	$ 4
Equity Method Investment Ownership Percentage Description	<div style="margin: 0in 0in 0.0001pt; font-family: "times new roman", serif; font-size: 10pt;">In no event may the Additional Purchase Right and/or the Participation Right be exercised to the extent it would cause the Investor or any of its affiliates to beneficially own 20% or more of the Company’s then outstanding common stock or hold shares with 20% or more of the voting power.</div><table border="0" style="width:100%; table-layout:fixed;" cellspacing="0" cellpadding="0"><tr><td></td></tr></table>
Offering [Member]
Class of Stock [Line Items]
Warrants Authorized For Issuance To Acquire Common Stock Shares Number				5,750,000
Proceeds From Issuance Or Sale Of Equity				$ 11,900,000
Stock Issued During Period, Shares, Other				2.25
Employee Stock Option [Member] \| Minimum [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period1									3 years
Employee Stock Option [Member] \| Maximum [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period1									4 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price									$ 2.10
General and Administrative Expense [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues									81,084
Consultant Plan [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance						200,524			200,524
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					10,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value									$ 3.50
Shares Reserved Unissued						149,774			149,774
General And Administrative Expense Related To Stock Grant									$ 35,000
Consultant Plan Expenses						$ 9,000	$ 26,000		$ 9,000	$ 33,000
Consultant Plan One [Member] \| Employee Stock Option [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						59,000	65,000		170,000	284,000
Equity Incentive Plan [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance						2,343,686			2,343,686
Increase Decrease Of Share Based Compensation Arrangement By Share Based Payment Award Percentage		10.00%
Share-based Compensation Outstanding - Reserved but unissued shares under the Plan						1,038,795			1,038,795		993,860
Shares Reserved Unissued						1,171,000			1,171,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period1									2 years 8 months 12 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options						$ 446,000			$ 446,000