Stock Based Compensation Plans - Schedule of Stock Option Activity (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2019	Jun. 30, 2019
Share-based Payment Arrangement [Abstract]
Number of Shares, Outstanding, Beginning Balance	341,195	368,000
Number of Shares, Granted
Number of Shares, Exercised		(26,805)
Number of Shares, Forfeited
Number of Shares, Exchanged
Number of Shares, Outstanding, Ending Balance	341,195	341,195
Number of Shares, Exercisable, Ending Balance	330,395	330,395
Number of Shares, Vested and expected to vest, Ending Balance	341,195	341,195
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 16.95	$ 17.21
Weighted Average Exercise Price, Granted
Weighted Average Exercise Price, Exercised		20.52
Weighted Average Exercise Price, Forfeited
Weighted Average Exercise Price, Exchanged
Weighted Average Exercise Price, Outstanding, Ending Balance	16.95	16.95
Weighted Average Exercise Price, Exercisable, Ending Balance	16.62	16.62
Weighted Average Exercise Price, Vested and expected to vest, Ending Balance	$ 16.95	$ 16.95
Weighted Average Remaining Life, Outstanding, Beginning Balance	3 years 26 days	4 years 2 months 1 day
Weighted Average Remaining Life, Outstanding, Ending Balance	2 years 9 months 25 days	3 years 26 days
Weighted Average Remaining Life, Exercisable, Ending Balance	2 years 8 months 2 days	2 years 11 months 1 day
Weighted Average Remaining Life, Vested and expected to vestEnding Balance	2 years 9 months 25 days	3 years 26 days
Aggregate Intrinsic Value, Outstanding, Beginning Balance	$ 4,680,000	$ 3,505,000
Aggregate Intrinsic Value, Outstanding, Ending Balance	4,369,000	4,680,000
Aggregate Intrinsic Value, Exercisable, Ending Balance	4,342,000	4,643,000
Aggregate Intrinsic Value, Vested and expected to vest, Ending Balance	$ 4,369,000	$ 4,680,000

Number of Shares, Exchanged.

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Weighted Average Exercise Price, Exchanged.

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Weighted Average Remaining Life, Outstanding, Ending Balance.

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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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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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- Definition

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

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