Common Stock and Warrants (Narrative) (Details) - USD ($)

1 Months Ended

3 Months Ended

6 Months Ended

Mar. 31, 2016

Mar. 31, 2015

Jun. 30, 2016

Jun. 30, 2015

Common Stock And Warrants Narrative Details

Exchange of warrants, shares

1,500,000

Cash on exercise of warrants

$ 3,300,000

Number of shares of common stock issued

928,000

Cash received from stock sale, before issuance costs

$ 6,900,000

$ 1,000,000

$ 2,600,000

Stock issuance costs

$ 650,000

$ 95,000

Warrant terms and provisions

In March 2016, we raised $6.9 million before issuance costs of approximately $650,000 from the sale of 4.1 million shares of common stock in an underwritten public offering.

During the three months ended March 31, 2015, we received gross proceeds of $1.0 million as part of an At-the-Market (ATM) agreement we entered into with Meyers Associates, L.P. in June 2014. We have completed sales under this agreement, having received total proceeds of $4.5 million before issuance costs of approximately $206,000 from the sale of 2.0 million shares of our common stock.

During the six months ended June 30, 2016, we received gross proceeds of $349,000 as part of an ATM agreement we entered into with Meyers Associates, L.P. in May 2015. Under the terms of the agreement, we may, from time to time, at our discretion, offer and sell shares of our common stock having an aggregate value of up to $6.0 million. As of June 30, 2016, we have received aggregate gross proceeds of approximately $2.6 million before issuance costs of approximately $95,000 from the sale of 928,000 shares of common stock.

During the six months ended June 30, 2015, we received $3.3 million from the exercise of warrants to purchase 1.5 million shares of common stock, which warrants were issued in connection with earlier financing transactions.