Additional Common Stock Shares Issued.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

+ References

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- Definition

Expense related to distribution, servicing and underwriting fees.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Number of shares issued under share-based payment arrangement.

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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jan. 01, 2020	Dec. 31, 2019	Jan. 01, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued	15,442,303	44,599,847		44,599,847			29,084,437
Public offering price of common stock	$ 4.75
Additional commons stock shares issued	3,789,473
Proceeds from issue of common stock	$ 129.1
Underwriter's discount and commission	8.2
Offering cost	$ 0.7
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.
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						1,163,377		965,603
Common stock available for future issuance		1,341,292		1,341,292
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		239,400	159,600	1,444,400	1,201,900
Stock options to purchase common stock aggregate fair value		$ 1.2	$ 0.7	$ 7.6	$ 6.9
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		0	0	25,928	20,132
Aggregate cash proceeds from sale of shares				$ 0.2	$ 0.1
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum ownership percentage for outstanding warrants to purchase shares of common stock to be exercised	19.99%
Pre Funded Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued	13,610,328
Public offering price of common stock	$ 4.7499