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Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Yearly Increase

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

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

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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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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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The amount of cash paid for commissions during the current period.

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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholder, which takes precedence over common stockholders in the event of liquidation and from issuance of rights to purchase common shares at a predetermined price.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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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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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Common Stock and Stockholders' Equity - Narrative 1 (Details) $ / shares in Units, $ in Thousands							12 Months Ended
	Jan. 22, 2020 shares	Dec. 24, 2019 USD ($) $ / shares shares	May 07, 2019 USD ($) $ / shares shares	May 03, 2019 USD ($) shares	Dec. 12, 2018 USD ($) shares	Oct. 15, 2018 USD ($) optionholder shares	Dec. 31, 2019 USD ($) vote shares	Dec. 31, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued (shares)							21,018,663	8,818,019
Common stock voting rights per share \| vote							1
Common shares reserved for future issuance (in shares)							87,640,000
Conversion ratio							0.08333
Exchange Offer shares available for exchange (in shares)						915,009
Number of optionholders \| optionholder						31
Restricted shares issued (in shares)						603,058
Stock-based compensation expenses \| $						$ 400	$ 2,288	$ 5,440
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares issued (in shares)						514,955
Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)				9,730,534
Number of securities called by warrants (in shares)			9,730,534
Sale of stock (usd per share) \| $ / shares			$ 1.205
Consideration received on transaction \| $				$ 16,700
Convertible preferred stock, shares issued upon conversion (in shares)			10
Warrant exercise period				5 years
Warrant exercise price (usd per share) \| $ / shares			$ 1.08
Milestone Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Consideration received on transaction \| $		$ 24,600
At The Moment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)					1,903,880
Consideration received on transaction \| $					$ 2,100
Commission fee rate					3.00%
Payments for commissions \| $					$ 100
Shares issued (in shares)								0
Preferred Class A \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)			4,158,980
Sale of stock (usd per share) \| $ / shares			$ 10.80
Nonvoting convertible preferred stock issued (in shares)			415,898
Preferred Class A \| Private Placement \| Warrant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock (usd per share) \| $ / shares			$ 0.125
Class A-2 Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion ratio		10
Class A-2 Convertible Preferred Stock \| Milestone Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)		3,288,390
Number of securities called by warrants (in shares)		32,883,900
Consideration received on transaction \| $		$ 26,000
Warrants, term		5 years
Warrant exercise price (usd per share) \| $ / shares		$ 0.666
Directors, Executive Officers and Employees \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)				526,083
Directors, Executive Officers and Employees \| Preferred Class A \| Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)			526,083
Proceeds from issuance of preferred warrants \| $			$ 600
Certain Directors and Executive Officers \| Class A-2 Convertible Preferred Stock \| Milestone Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)		121,581
Number of securities called by warrants (in shares)		1,215,810
Consideration received on transaction \| $		$ 1,000
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant (in shares)							403,939
Common shares reserved for future issuance (in shares)							3,226,804
Subsequent Event \| 2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares available (in shares)	4,166,860
Yearly authorized increase	5.00%