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Stock-Based Compensation - Summary of Stock Options Outstanding (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	May 16, 2017
Options Outstanding, Number	3,148,743	200,000
Options Exercisable, Number	1,689,902
Exercise Price One [Member]
Range of Exercise Prices, Upper	$ 5.00
Options Outstanding, Number	3,084,252
Options Outstanding, Weighted Average Remaining Contractual Term (in years)	9 years 2 months 12 days
Options Outstanding, Weighted Average Exercise Price	$ 2.34
Options Exercisable, Number	1,625,807
Options Exercisable, Weighted Average Remaining Contractual Term (in years)	9 years 2 months 12 days
Options Exercisable, Weighted Average Exercise Price	$ 2.34
Exercise Price Two [Member]
Range of Exercise Prices, Upper	81.90
Range of Exercise Prices, Lower	$ 5.00
Options Outstanding, Number	64,491
Options Outstanding, Weighted Average Remaining Contractual Term (in years)	7 years
Options Outstanding, Weighted Average Exercise Price	$ 19.00
Options Exercisable, Number	64,095
Options Exercisable, Weighted Average Remaining Contractual Term (in years)	7 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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- Definition

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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