Stockholders' Equity - Fair Value (Details)	3 Months Ended
Dec. 31, 2021
Employee Stock Option
Stockholders' Equity
Dividend yield percentage	0.00%
Expected volatility, minimum percentage	58.70%
Expected volatility, maximum percentage	61.20%
Risk free interest rate, minimum percentage	1.10%
Risk free interest rate, maximum percentage	1.30%
Stock Options, Restricted Stock Units And Stock Appreciation Rights, Market-Based
Stockholders' Equity
Dividend yield percentage	0.00%
Expected volatility, minimum percentage	57.20%
Expected volatility, maximum percentage	62.90%
Risk free interest rate, minimum percentage	1.10%
Risk free interest rate, maximum percentage	1.50%
Minimum \| Employee Stock Option
Stockholders' Equity
Expected term	4 years 6 months
Minimum \| Stock Options, Restricted Stock Units And Stock Appreciation Rights, Market-Based
Stockholders' Equity
Expected holding period percentage	29.40%
Maximum \| Employee Stock Option
Stockholders' Equity
Expected term	5 years
Maximum \| Stock Options, Restricted Stock Units And Stock Appreciation Rights, Market-Based
Stockholders' Equity
Expected holding period percentage	100.00%

Share-Based Compensation Arrangement By Share-Based Payment Award, Fair Value Assumptions, Expected Holding Period

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- Definition

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

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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.

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- Definition

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

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

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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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- 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
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