Fair Value Measurements - Additional Information (Details) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Warrants options term		3 years
SAFEs [Member]
Warrants options risk free rate		30.00%
With IPO [Member]
Assumed total equity valuation	$ 3,300
Warrants options term	1 month 15 days
Warrants options volatility	76.20%
Warrants options risk free rate	0.08%
Percentage of occurrence of ipo	95
No IPO [Member]
Assumed total equity valuation	$ 1,900
Warrants options term	2 years 1 month 15 days
Warrants options volatility	72.10%
Warrants options risk free rate	0.13%
Weightage being assigned to the value derived in the IPO	5
Warrant [Member]
Assumed total equity valuation		$ 640
Warrants options volatility		49.60%
Warrants options risk free rate		1.62%
Warrant [Member] \| No IPO [Member]
Warrants options risk free rate	35.00%	35.00%

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- Definition

Warrants Assumed Total Equity Valuation

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- Definition

Weightage being assigned to the value derived in the IPO

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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.

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- Definition

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

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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
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-Name Accounting Standards Codification
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