Stock-Based Compensation - Evergreen provision (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
2019 Plan
Number of Options
Period of automatic increase in shares reserved	10 years
Percentage of the common shares outstanding (as a percent)	4.00%
2019 Plan \| Stock options
Number of Options
Vested	25,000	42,862
Forfeited, nonvested	270,287	0
Stock Plan 2018 And 2019 Plans
Unrecognized share-based compensation
Unrecognized share-based compensation cost	$ 1.0
Unrecognized share-based compensation - Weighted average period	1 year 9 months 18 days
Stock Plan 2018 And 2019 Plans \| Stock options
Number of Options
Aggregate maximum number of shares of common stock that may be issued	5,172,646
Maximum \| 2019 Plan
Number of Options
Aggregate maximum number of shares of common stock that may be issued	6,680,000

The period over which the shares reserved for further issuance under share based compensation will increase annually.

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- References

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

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- Definition

Number of options vested.

+ References

No definition available.

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