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Stockholders' Equity - Grants and Expense (Details) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
	May 08, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
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
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 316,000		$ 316,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				259,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		$ 131,000		$ 131,000
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 1.80		$ 1.80
Warrants Intrinsic Value Outstanding		$ 0		$ 0
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		80,000		80,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number		1,150,375		1,150,375		587,962
Stock Issued During Period In Lieu of Cash Bonus						159,100
Warrants and Rights Remaining Term				1 year 4 months 21 days
Incentive Stock Options [Member]
Class of Stock [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 146,000		$ 146,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term2				10 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 2.25
Allocated Share-based Compensation Expense		$ 24,000		$ 183,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period1				2 years
Incentive Stock Options [Member] \| Minimum [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 1.16
Consultant Plan [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance		253,367		253,367
Increase Decrease Of Share Based Compensation Arrangement By Share Based Payment Award Percentage				1.00%
Consultant Plan Expenses		$ 4,000	$ 9,000	$ 11,000	$ 26,000
Shares Reserved Unissued		192,617		192,617
Consultant Plan [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				329,000
Consultant Plan Two [Member]
Class of Stock [Line Items]
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				$ 1.44
Share Based Compensation Arrangement By Share Based Payment Award Options Value Grants In Period Weighted Average Grant Date Fair Value				$ 14,000
2011 Equity Incentive Plan [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				258,618
Non-Qualified Stock Option [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				341,382
Equity Incentive Plan [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	1,231,593
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	4,004,214
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	15.00%
Common Stock, Capital Shares Reserved for Future Issuance		4,004,589		4,004,589
Increase Decrease Of Share Based Compensation Arrangement By Share Based Payment Award Percentage				15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				1,298,718
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term2				10 years
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 1		$ 1
Allocated Share-based Compensation Expense		$ 58,000	59,000	$ 274,000	170,000
Share-based Compensation Outstanding - Reserved but unissued shares under the Plan		2,115,670		2,115,670		880,277
Shares Reserved Unissued		1,297,040		1,297,040
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period1				1 year 8 months 12 days
Equity Incentive Plan [Member] \| Minimum [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 0.87
Equity Incentive Plan [Member] \| Maximum [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 2.25
Equity Incentive Plan [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Estimated common stock subject to options issued				381,000
Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				258,618
Equity Incentive Plan [Member] \| Director [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				381,000
Equity Incentive Plan [Member] \| Other Employees [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				500,000
Equity Incentive Plan [Member] \| Board of Directors [Member]
Class of Stock [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 34,000		$ 34,000
Equity Incentive Plan [Member] \| Board of Directors [Member] \| Incentive Stock Options [Member]
Class of Stock [Line Items]
Allocated Share-based Compensation Expense		$ 34,000	$ 0	$ 103,000	$ 0