Stock-Based Compensation - Changes in stock options (Details) - Time-based stock option awards - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Number of shares
Outstanding Options at beginning of period (in shares)	579,370
Granted (in shares)	1,140,873
Forfeited (in shares)	(16,842)
Outstanding Options at end of period (in shares)	1,703,401	579,370
Exercisable Options at end of period (in shares)	2,807
Weighted Average Exercise Price per Share
Outstanding Options at beginning of period (in dollars per share)	$ 9.44
Granted (in dollars per share)	4.51
Forfeited (in dollars per share)	10.83
Outstanding Options at end of period (in dollars per share)	$ 6.15	$ 9.44
Weighted Average Contractual Life (Years)
Outstanding Options (in years)	9 years 8 months 5 days	9 years 5 months 23 days

No Definition

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- 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

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Weighted average price of options that were either forfeited or expired.

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-Publisher FASB
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-Topic 718
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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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Number of options outstanding, including both vested and non-vested options.

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

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.

+ References

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