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Stock-based Compensation - Stock Option Activity (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares
Options [Roll Forward]
Balance as of December 31, 2020 (in share) | shares	531,336
Granted (in share) | shares	159,939
Cancelled/forfeited (in share) | shares	(12)
Balance as of March 31, 2021 (in share) | shares	691,263
Vested as of March 31, 2021 | shares	159,140
Vested and expected to be vested as of March 31, 2021 | shares	636,442
Weighted Average Exercise Price [Roll Forward]
Balance as of December 31, 2020 (in dollars per share) | $ / shares	$ 10.01
Granted (in dollars per share) | $ / shares	3.64
Cancelled/forfeited (in dollars per share) | $ / shares	41,300.00
Balance as of March 31, 2021 (in dollars per share) | $ / shares	7.82
Vested as of March 31, 2021 | $ / shares	24.91
Vested and expected to be vested as of March 31, 2021 | $ / shares	$ 8.14
Aggregate Intrinsic Value [Roll Forward]
Balance as of March 31, 2021 | $	$ 149
Vested as of March 31, 2021 | $	42
Vested and expected to be vested as of March 31, 2021 | $	$ 140

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- Definition

Share based compensation arrangement by share based payment award options aggregate intrinsic value roll forward1.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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Number of fully vested and expected to vest exercisable options that may 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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. 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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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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