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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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.

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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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.

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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 (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809

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Equity and Equity Compensation Plans - Summary of Value Assumptions (Details) - $ / shares			12 Months Ended
	Jul. 01, 2021	Jan. 01, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life			0 years	0 years	6 years 6 months
Volatility			0.00%	0.00%	33.76%
Risk-free interest rate			0.00%	0.00%	2.12%
Dividend yield			0.00%	0.00%	0.00%
Weighted-average grant date fair value (in dollars per share)			$ 0	$ 0	$ 3.22
2017 Employee Stock Purchase Plan \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	6 months	6 months
Volatility	74.50%	61.49%
Risk-free interest rate	0.05%	0.09%
Dividend yield	0.00%	0.00%
Weighted-average grant date fair value (in dollars per share)	$ 22.79	$ 21.41