Note 9 - Warrants	6 Months Ended
Jun. 30, 2019
Notes to Financial Statements
Warrants Disclosure [Text Block]	9 . Warrants Loan Agreement Warrants In connection with the Loan Agreement, on May 30, 2019, the Company issued warrants to the Lender and its affiliates, which are exercisable for an aggregate of 176,679 shares of the Company’s common stock with a per share exercise price of $2.83, or the Warrants. The Warrants may be exercised on a cashless basis. The Warrants are exercisable for a term beginning on the date of issuance and ending on the earlier to occur of ten years from the date of issuance or the consummation of certain acquisitions of the Company as set forth in the Warrants. The number of shares for which the Warrants are exercisable and the associated exercise price are subject to certain proportional adjustments as set forth in the Warrants. The Company estimated the fair value of these Warrants as of the issuance date to be $0.4 million, which was used in estimating the fair value of the debt instrument and was recorded as equity. The fair value of the Warrants was calculated using the Black-Scholes option-valuation model, and was based on the strike price of $2.83, the stock price at issuance of $2.66, the ten -year contractual term of the warrants, a risk-free interest rate of 2.22%, expected volatility of 80.22% and 0% expected dividend yield. As of June 30, 2019, warrants to purchase 176,679 shares of common stock issued to the Lender and its affiliates had not been exercised and were still outstanding. These warrants expire in May 2029.

Warrants

Loan Agreement Warrants

In connection with the Loan Agreement, on

May 30, 2019,

the Company issued warrants to the Lender and its affiliates, which are exercisable for an aggregate of

176,679

shares of the Company’s common stock with a per share exercise price of

$2.83,

or the Warrants. The Warrants

may

be exercised on a cashless basis. The Warrants are exercisable for a term beginning on the date of issuance and ending on the earlier to occur of

ten

years from the date of issuance or the consummation of certain acquisitions of the Company as set forth in the Warrants. The number of shares for which the Warrants are exercisable and the associated exercise price are subject to certain proportional adjustments as set forth in the Warrants.

The Company estimated the fair value of these Warrants as of the issuance date to be

$0.4

million, which was used in estimating the fair value of the debt instrument and was recorded as equity. The fair value of the Warrants was calculated using the Black-Scholes option-valuation model, and was based on the strike price of

$2.83,

the stock price at issuance of

$2.66,

the

ten

-year contractual term of the warrants, a risk-free interest rate of

2.22%,

expected volatility of

80.22%

and

expected dividend yield.

As of

June 30, 2019,

warrants to purchase

176,679

shares of common stock issued to the Lender and its affiliates had

not

been exercised and were still outstanding. These warrants expire in

May 2029.