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Stock-Based Compensation - Summary of Stock Options Outstanding (Details)	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Options Outstanding, Number | shares	3,885,892
Options Exercisable, Number | shares	2,469,033
Exercise Price One [Member]
Range of Exercise Prices, Upper	$ 5.00
Options Outstanding, Number | shares	3,821,470
Options Outstanding, Weighted Average Remaining Contractual Term (in years)	8 years 4 months 24 days
Options Outstanding, Weighted Average Exercise Price	$ 2.47
Options Exercisable, Number | shares	2,404,611
Options Exercisable, Weighted Average Remaining Contractual Term (in years)	8 years
Options Exercisable, Weighted Average Exercise Price	$ 2.55
Exercise Price Two [Member]
Range of Exercise Prices, Upper	81.90
Range of Exercise Prices, Lower	$ 5.00
Options Outstanding, Number | shares	64,422
Options Outstanding, Weighted Average Remaining Contractual Term (in years)	6 years
Options Outstanding, Weighted Average Exercise Price	$ 19.00
Options Exercisable, Number | shares	64,422
Options Exercisable, Weighted Average Remaining Contractual Term (in years)	6 years
Options Exercisable, Weighted Average Exercise Price	$ 19.00

X

- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

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

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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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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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