Stock-based Compensation and Equity Grants - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
Jul. 13, 2020	Sep. 30, 2020	Sep. 30, 2019
Number of Shares
Outstanding at September 30, 2019 (in shares)		2,134
Granted (in shares)		750
Exercised (in shares)		(395)
Cancelled (in shares)		(360)
Outstanding at September 30, 2020 (in shares)		2,129	2,134
Weighted Average Exercise Price
Outstanding at September 30, 2019 (in dollars per share)		$ 4.36
Granted (in dollars per share)		6.74
Exercised (in dollars per share)		0.99
Cancelled (in dollars per share)		2.89
Outstanding at September 30, 2020 (in dollars per share)		$ 0	$ 4.36
Weighted Average Remaining Contractual Term (in years)
Outstanding at September 30, 2020		7 years 4 months 24 days	5 years 10 months 24 days
Aggregate Intrinsic Value
Outstanding at the September 30, 2019		$ 4,815
Options outstanding at September 30, 2020		$ 6,583	$ 4,815
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility rate	50.00%	50.00%
Term		10 years
Stock price threshold term		10 days

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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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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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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.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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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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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.

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