Equity-Based Compensation - Stock options, fair value assumptions (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Equity-Based Compensation
Fair value of options granted (in dollars per share)	$ 8.83	$ 4.32
Stock options granted during the period (in shares)	874,830
Equity-based compensation expense	$ 2,029	$ 794
Stock options
Equity-Based Compensation
Risk-free interest rate, minimum (as a percent)	1.47%	0.63%
Risk-free interest rate, maximum (as a percent)	1.89%	1.15%
Expected dividend yield (as a percent)	0.00%	0.00%
Expected volatility, minimum (as percentage)	80.75%	84.61%
Expected volatility, maximum (as percentage)	80.92%	85.26%
Stock options \| Minimum
Equity-Based Compensation
Expected term (in years)	6 years	5 years 6 months 7 days
Stock options \| Maximum
Equity-Based Compensation
Expected term (in years)	6 years 29 days	10 years
Stock options, excluding performance-based awards
Equity-Based Compensation
Total unrecognized compensation cost	$ 25,400
Weighted-average period for unrecognized compensation cost to be recognized	3 years 14 days
Stock options, vesting based on performance
Equity-Based Compensation
Equity-based compensation expense	$ 0
Stock options, vesting based on performance \| Maximum
Equity-Based Compensation
Total unrecognized compensation cost	$ 100

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

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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 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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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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

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

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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.

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