Stock-based Compensation - Stock Options Outstanding (Details) - Stock Options	3 Months Ended
Dec. 31, 2019 $ / shares shares
Shares
Outstanding at beginning of period (shares) \| shares	523,754
Granted (shares) \| shares	0
Exercised (shares) \| shares	(123,367)
Forfeited (shares) \| shares	(100)
Outstanding at end of period (shares) \| shares	400,287
Exercisable at end of period (shares) \| shares	363,931
Vested or expected to vest in the future (shares) \| shares	398,358
Weighted Average Exercise Price
Outstanding at beginning of period (in dollars per share) \| $ / shares	$ 14.34
Granted (in dollars per share) \| $ / shares	0.00
Exercised (in dollars per share) \| $ / shares	11.08
Forfeited (in dollars per share) \| $ / shares	15.47
Outstanding at end of period (in dollars per share) \| $ / shares	15.35
Exercisable at end of period (in dollars per share) \| $ / shares	15.64
Vested or expected to vest in the future (in dollars per share) \| $ / shares	$ 15.38

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.

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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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- Definition

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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. 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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- Definition

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

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