Stock-based Compensation - Stock Options Outstanding (Details) - Stock options - $ / shares	6 Months Ended
Mar. 31, 2021
Shares
Outstanding at beginning of period (shares)	392,465
Exercised (shares)	(167,435)
Outstanding at end of period (shares)	225,030
Exercisable at end of period (shares)	218,528
Weighted Average Exercise Price
Outstanding at beginning of period (in USD per share)	$ 15.47
Exercised (in USD per share)	13.03
Outstanding at end of period (in USD per share)	17.81
Exercisable at end of period (in USD per share)	$ 18.05

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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- Definition

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.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB
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- Definition

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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No definition available.

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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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- Definition

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

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- Definition

Number of share options (or share units) exercised during the current period.

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