Note 9 - Equity and Stock-based Compensation (Details Textual)			1 Months Ended	12 Months Ended
	May 28, 2018 USD ($) shares	May 05, 2016 USD ($) $ / shares shares	Jun. 30, 2018 USD ($) shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Sep. 30, 2018 $ / shares	Sep. 17, 2018 shares	Aug. 04, 2016 shares
Authorized Shares, Common and Preferred				101,000,000
Common Stock, Shares Authorized				100,000,000	100,000,000
Common Stock, Par or Stated Value Per Share | $ / shares				$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized				1,000,000	1,000,000
Preferred Stock, Par or Stated Value Per Share | $ / shares				$ 0.0001	$ 0.001
Stock Issued During Period, Shares, New Issues	1,000,000		1,000,000
Preferred Stock, Liquidation Preference, Value | $				$ 29,038,000	$ 29,038,000
Proceeds from Issuance of Common Stock | $	$ 500,000		$ 500,000	500,000	2,922,500
Issuance of Options to Settle Accrued Compensation Liabilities | $				$ 451,250
The 2016 Omnibus Plan [Member]
Evergreen Provision, Increase in Number of Shares Authorized Calculation, Percentage Amount of Prior Year's Reserved Shares								6.00%
Evergreen Provision, Maximum Limit of Increase to Authorized Shares								1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				1,685,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				1,140,626	56,250
Share-based Compensation Arrangement by Share-based Payment Award, Options, Granted in Period, Fair Value | $				$ 58,000	$ 8,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $				$ 7,000	$ 54,600
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				0	0
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total | $				$ 0	$ 0
Warrants Issued to Investors [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights							466,666
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares						$ 0.15
Common Stock [Member]
Stock Issued During Period, Shares, New Issues				1,000,000	12,800,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		6,180,000
Additional Paid-in Capital [Member] | The 2016 Omnibus Plan [Member]
Issuance of Options to Settle Accrued Compensation Liabilities | $				$ 451,250
Maximum [Member] | Common Stock [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares		$ 0.75
Minimum [Member] | Common Stock [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares		$ 0.50
Series A Preferred Stock [Member]
Preferred Stock, Shares Authorized		29,038
Preferred Stock, Par or Stated Value Per Share | $ / shares		$ 0.0001
Stock Issued During Period, Shares, New Issues		29,038
Preferred Stock, Liquidation Preference, Value | $		$ 29,038,000
Preferred Stock, Voting Rights, Number of Votes Per Share		5
Preferred Stock, Restrictions, Debt Ceiling Other Than for Working Capital Purposes | $		$ 3,000,000
Series A Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Voting Rights, Percentage of Voting Rights of Capital Stock		1.00%