Note 17 - Subsequent Events (Details Textual) - USD ($)			3 Months Ended
	May 03, 2020	Apr. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Apr. 27, 2020	Apr. 16, 2020	Dec. 31, 2019
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.01				$ 0.01
Class of Warrant or Right, Exercised During Period (in shares)			299,000
Proceeds from Warrant Exercises			$ 201,000
The June 2019 Warrants [Member]
Class of Warrant or Right, Exercised During Period (in shares)			228,571
Subsequent Event [Member]
Share-based Payment Arrangement, Percent of Outstanding Common Stock Exercisable						12.00%
Stock Issued In Connection with Exercise of Warrants, Shares (in shares)		571,428
Proceeds from Paycheck Protection Program Under CARES Act	$ 900,505
Subsequent Event [Member] | The June 2019 Warrants [Member]
Class of Warrant or Right, Exercised During Period (in shares)		571,428
Proceeds from Warrant Exercises		$ 497,000
Subsequent Event [Member] | At the Market Offering Agreement [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.01
Sale of Stock, Maximum Issuable Stock, Value					$ 4,302,137
Sale of Stock, Commission Fee, Percent					3.00%