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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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

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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-Topic 718
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Stock-Based Compensation - Fair Value Assumptions (Detail)	1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			5 years 6 months	4 years
Chief Executive Officer \| 2017 Equity Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		3.01%	3.01%
Expected term (in years)		4 years 1 month 6 days
Expected volatility		70.00%	70.00%
Expected dividend yield		0.00%	0.00%
Chief Executive Officer \| 2017 Equity Incentive Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years 4 months 24 days
Chief Executive Officer \| 2017 Equity Incentive Plan \| Minimum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			3 years 4 months 24 days
Chief Executive Officer \| 2017 Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	4 years 1 month 6 days
Chief Executive Officer \| 2017 Equity Incentive Plan \| Maximum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			4 years 1 month 6 days