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.

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

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- Definition

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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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.

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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.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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.

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

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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.

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No definition available.

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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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- Definition

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

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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		9 Months Ended
	Jul. 31, 2020	Apr. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 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	44,692,030		44,692,030			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		$ 129.0
Underwriter's discount and commission		8.2
Offering cost		$ 0.8
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			884,328		884,328
2016 Equity Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option to purchase an aggregate of common stock shares	228,200		228,200		228,200
Total stock-based compensation expense					$ 1.9
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			33,965	24,772	59,893	44,904
Aggregate cash proceeds from sale of shares			$ 0.2	$ 0.2	$ 0.4	$ 0.3
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