Stock-Based Compensation - Schedule of Estimate of the Fair Value of Stock Option (Detail)	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Schedule of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Risk-free interest rate	0.90%
Risk-free interest rate minimum		2.00%
Risk-free interest rate maximum		2.10%
Expected term in years	7 years
Expected volatility	70.00%	80.00%
Maximum [Member]
Schedule of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Expected term in years		10 years
Minimum [Member]
Schedule of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Expected term in years		6 years 4 months 17 days

Schedule of share based payment award stock options valuation assumptions [Line Items].

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- Definition

The estimated measure of the 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.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
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