Stockholder's Equity - Schedule of 2017 Plan Valuation Assumptions (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Mar. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of stock on measurement date (in dollars per share)			$ 19.18
2017 Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.67%	2.47%
Risk-free interest rate, maximum	2.57%	3.05%
Dividend yield	0.00%	0.00%
Volatility factor, minimum	104.00%	121.00%
Volatility factor, maximum	139.00%	324.00%
2017 Plan \| Employee Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of stock on measurement date (in dollars per share)	$ 11.26	$ 14.31
Term (years)	5 years 6 months	5 years 6 months
2017 Plan \| Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of stock on measurement date (in dollars per share)	$ 15.65	$ 24.84
Term (years)	6 years 2 months 30 days	10 years

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the maximum 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

No definition available.

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The estimated measure of the minimum 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

No definition available.

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- Definition

The maximum 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

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

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.

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No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ 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
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-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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