Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 14
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Organization - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Subsidiary, Sale of Stock [Line Items]
Gross proceeds from issuance of common stock		$ 48,641	$ 0
Deferred issuance costs, net	$ 200	200
Cash, cash equivalents and short-term investments	90,200	90,200
Accumulated deficit	$ 242,546	$ 242,546		$ 198,853
June Offering
Subsidiary, Sale of Stock [Line Items]
Number of shares sold in public offering (in shares)	13,800,000
Price of shares sold in public offering (in dollars per share)	$ 3.75	$ 3.75
Gross proceeds from issuance of common stock	$ 51,800
Net proceeds from issuance of common stock	$ 48,400
Over-Allotment Option
Subsidiary, Sale of Stock [Line Items]
Number of shares sold in public offering (in shares)	1,800,000