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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Number of new stock issued during the period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The Company and Basis of Presentation (Follow-On Offering) (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Feb. 12, 2018	Sep. 08, 2016	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Aug. 04, 2016
Sale of Stock
Issuance of stock (in shares)			3,592,858
Common Stock, Par Value (in dollar per share)			$ 0.001		$ 0.001	$ 0.001
Offering costs			$ 1,949	$ 1,072
Follow On Offering
Sale of Stock
Issuance of stock (in shares)	3,142,858
Share price (in dollars per share)	$ 7.00
Net proceeds	$ 23,100
Offering costs			$ 2,100
Overallotment
Sale of Stock
Issuance of stock (in shares)	450,000	27,755
Share price (in dollars per share)		$ 10.00