Stock-Based Compensation - Schedule Of Outstanding Stock Options Currently Exercisable, Vested And Expected To Vest (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Stock options outstanding	391,100	207,759
Stock options outstanding, Weighted Average Remaining Contractual Life (in Years)	7 years 9 months 21 days
Stock options outstanding, Weighted Average Exercise Price per Share	$ 36.71	$ 24.43
Stock options outstanding, Aggregate Intrinsic Value	$ 34,236
Exercisable, Number of Shares	119,734
Exercisable, Weighted Average Remaining Contractual Life (in Years)	7 years 1 month 9 days
Exercisable, Weighted Average Exercise Price per Share	$ 25.38
Exercisable, Aggregate Intrinsic Value	$ 11,683
Vested and expected to vest, Number of Shares	368,503
Vested and expected to vest, Weighted Average Remaining Contractual Life (in Years)	7 years 9 months 7 days
Vested and expected to vest, Weighted Average Exercise Price per Share	$ 36.04
Vested and expected to vest, Aggregate Intrinsic Value	$ 32,477

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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-Publisher FASB
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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