Number of stock compensation plans.

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Value of stock related to Restricted Stock Awards issued during the period, net of the stock value of such awards forfeited.

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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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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Stock-Based Compensation - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) Plan $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock compensation plans \| Plan	3
Common stock reverse stock split ratio	0.05555555555
Common stock reverse stock split description	one-for-eighteen
Number of options outstanding	3,621,479	91,403	49,798
Range of exercise prices \| $ / shares	$ 10.63	$ 139.96	$ 233.45
Aggregate intrinsic value of options exercised \| $	$ 0	$ 0
Unrecognized stock-based compensation expense \| $	$ 17,100,000
Unrecognized stock-based compensation expense, recognized over estimated weighted average period	2 years 8 months 12 days
Stock-based compensation expense \| $	$ 3,171,000	$ 1,308,000
PRSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense \| $	$ 0
Number of shares vested	3,059
Value of shares vested \| $	$ 205,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices \| $ / shares	$ 0.96
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices \| $ / shares	$ 2,147
2020 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized for issuance	4,860,000
Number of options outstanding	692,956
Options granted, expiration period	10 years
Stock awards available for grant	4,167,044
Stock awards available for grant	4,167,044
Common stock, number of shares reserved for issuance	4,860,000
2014 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized for issuance	0
Number of options outstanding	126,974
Options granted, expiration period	10 years
Common stock, number of shares reserved for issuance	0
2007 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding	1,151
Options granted, expiration period	10 years