Stock Based Compensation (Details)	9 Months Ended
Sep. 30, 2019 shares
Stock-based compensation
Vesting period (in years)	4 years
2019 Plan
Stock-based compensation
Aggregate number of shares of our common stock initially reserved for issuance	2,919,872
Vesting period (in years)	10 years
Percentage of common stock outstanding	4.00%
ESPP
Stock-based compensation
Aggregate number of shares issued	133,580
Vesting period (in years)	10 years
Percentage of common stock outstanding	1.00%

Percentage of total common stock outstanding.

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Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Number of shares issued under share-based payment arrangement.

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-Topic 718
-SubTopic 10
-Section 50
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