Number of warrants exercised.

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Weighted average remaining life of warrants or rights outstanding.

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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 warrants or rights outstanding.

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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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Amount of cost to be recognized for option under share-based payment arrangement.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Share-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended			9 Months Ended
	Jun. 30, 2020	Jun. 22, 2020	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 22, 2020	Apr. 22, 2020	Dec. 31, 2019	Aug. 03, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding			1,650,000			1,650,000				8,995,906
Share-based payments expense			$ 3,300,000		$ 2,500,000	$ 8,800,000	$ 6,500,000
Unrecognized compensation expense related to non-vested share options			$ 7,300,000			7,300,000
Total fair value of vested shares						$ 8,800,000	6,000,000.0
Weighted average exercise price of warrants			$ 1.65			$ 1.65			$ 0.5869
Weighted average remaining life of warrants						4 years 3 months 18 days
Cash received from options exercised						$ 0	0
Proceeds from exercise of warrants and issuance of common stocks						$ 39,128,000	$ 2,500,000
Weighted average period for recognition related to non-vested stock options						1 year 2 months 12 days
2010 Stock Incentive Plan ("the Plan")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance			31,500,000			31,500,000		56,800,000			4,000,000.0
Number of options available for issuance			500,000			500,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of non-vested restricted shares			29,586			29,586
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding to purchase shares of common stock			26,329,067			26,329,067				14,936,726
$5.0 million YA II PN*
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding			0			0				1,000,000
Weighted average exercise price of warrants			$ 1.00			$ 1.00
Warrants exercised		1,700,000		1,000,000.0
Proceeds from exercise of warrants and issuance of common stocks		$ 2,500,000		$ 1,000,000.0
Warrants, ID Venturas
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercised	5,300,000
Proceeds from exercise of warrants and issuance of common stocks	$ 3,100,000