Maximum ownership percentage for outstanding warrants to purchase shares of common stock to be exercised.

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Period after notice received by company maximum ownership percentage to be effective description.

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Reduction in exercise price of each warrant from public offering price for pre-funded warrants per share

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- Definition

Share-based compensation arrangement by share-based payment award, additional number of shares available for grant.

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The maximum annual increase in the number of shares reserved under the plan as a proportion of outstanding common stock.

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- Definition

Share based compensation arrangement by share based payment award shares issued in period fair value.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Aggregate number of common shares reserved for future issuance.

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Expense related to distribution, servicing and underwriting fees.

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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 additional capital contribution to the entity.

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The cash inflow associated with the amount received from the stock plan during the period.

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The cash inflow associated with the amount received from holders exercising their stock warrants.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Gross number of share options (or share units) granted during the period.

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Number of share instruments newly issued under a share-based compensation plan.

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Number of new stock issued during the period.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended
	Feb. 28, 2019	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Jan. 01, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Net proceeds from sale of common stock	$ 64,500,000
Underwriting discounts and commissions	4,100,000
Offering costs	$ 400,000
Reduction in exercise price of each warrant from public offering price for pre-funded warrants per share	$ 0.0001
Maximum ownership percentage for outstanding warrants to purchase shares of common stock to be exercised	4.99%
Period after notice received by company maximum ownership percentage to be effective description		The revised Maximum Ownership Percentage would be effective 60 days after the notice is received by the Company.
Proceeds from Warrant Exercises		$ 0
2016 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding share of common stock		4.00%
Additional number of shares available for issuance				965,603	666,807
Common stock available for future issuance		1,499,373
2016 Equity Incentive Plan \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option to purchase an aggregate of common stock shares		1,042,300	829,500
Stock options to purchase common stock aggregate fair value		$ 6,200	$ 3,900
2016 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option to purchase an aggregate of common stock shares		20,132	30,937
Aggregate cash proceeds from sale of shares		$ 100,000	$ 100,000
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issued		4,625,000
Follow-on Public Offering \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issued	4,625,000
Public offering price	$ 8.00
Public offering price of warrant	$ 7.9999
Follow-on Public Offering \| Common Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants to purchase shares	4,000,000
Underwriters' Over-allotment Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issued	1,125,000