Purchase Agreement, Controlled Equity Offering and Public Offering of Common Stock (Tables)

3 Months Ended

Mar. 31, 2018

Purchase Agreement Controlled Equity Offering And Public Offering Of Common Stock [Abstract]

Schedule of Total Sales under 2017 Sales Agreement

The following table summarizes the total sales under the 2017 Sales Agreement for the periods indicated (in thousands, except per share amounts):

	2017 Sales Agreement
	Year Ended December 31, 2017
Total shares of common stock sold		15,998.5
Average price per share	$	3.13
Gross proceeds	$	50,000
Commissions earned by Stifel	$	1,500
Other issuance costs	$	97