Intrinsic value of equity-based compensation awards not vested. Stock units.

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- Definition

Intrinsic value of equity-based compensation awards not vested. Stock units

+ References

No definition available.

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- Definition

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

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- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

+ References

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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No definition available.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-based compensation - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Jun. 11, 2020	Jun. 07, 2018	Sep. 17, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share based compensation expense	$ 600	$ 900
Common stock reserved for issuance	2,786,986
Options granted	254,700	524,800	3,164,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 1,400		$ 700
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	100		$ 300
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 0	$ 11,100
Stock option vesting period	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	7,043,259
Minimum
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Contractual term	3 years
Maximum
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Contractual term	10 years
2014 Stock Incentive Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Common stock reserved for issuance						3,000,000
Share-based compensation arrangement by share based payment award percentage of fair market Person holding more then 10% voting stock						110.00%
2018 Stock Incentive Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Common stock reserved for issuance					4,000,000
Share-based compensation arrangement by share based payment award percentage of fair market Person holding more then 10% voting stock					110.00%
2020 Stock Incentive Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Common stock reserved for issuance				3,000,000
Share-based compensation arrangement by share based payment award percentage of fair market Person holding more then 10% voting stock				110.00%