Share-based Payments - Fair Value of Options Issued (Details) - Stock options	12 Months Ended
Dec. 31, 2020 $ / shares $ / shares	Dec. 31, 2019 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price at grant date (in dollars per share)	$ 6.96
Exercise price (per option) (in dollars per share)	$ 6.96
Risk-free interest rate	43.00%
Expected life of options (in years)	5 years	5 years
Expected annualized volatility	91.00%	82.00%
Expected dividend yield	0.00%	0.00%
Weighted average Black-Scholes value at grant date (per option) (in dollars per share)	$ 4.84	$ 13.03
Forfeiture rate	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price at grant date (in dollars per share)		$ 15.34
Exercise price (per option) (in dollars per share)		$ 15.34
Risk-free interest rate		1.39%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price at grant date (in dollars per share)		$ 24.75
Exercise price (per option) (in dollars per share)		$ 24.75
Risk-free interest rate		1.62%

Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Weighted Average Grant Date Fair Value

+ References

No definition available.

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

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

Price of a single share of a number of saleable stocks of a company.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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