Stock Based Compensation (Schedule of Stock Option Activity) (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2018	Jun. 30, 2018
Number of Shares Subject To Options
Balance at July 1, 2018	222,854
Granted	500
Exercised	(9,199)
Forfeited or expired	(1,055)
Outstanding at September 30, 2018	213,100	222,854
Vested or expected to vest at September 30, 2018	200,057
Exercisable at September 30, 2018	125,800
Weighted Average Exercise Price
Balance at July 1, 2018	$ 24.29
Granted	25.70
Exercised	21.75
Forfeited or expired	24.38
Outstanding at September 30, 2018	24.40	$ 24.29
Vested or expected to vest at September 30, 2018	24.43
Exercisable at September 30, 2018	$ 24.76
Weighted Average Remaining Contractual Term
Outstanding	6 years 1 month 20 days	6 years 3 months 4 days
Granted	9 years 9 months 7 days
Vested or expected to vest at September 30, 2018	5 years 11 months 19 days
Exercisable at September 30, 2018	4 years 4 months 9 days
Aggregate Intrinsic Value
Outstanding atSeptember 30, 2018	$ 116,905
Vested or expected to vest at September 30, 2018	1,091,877
Exercisable at September 30, 2018	$ 645,746

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Weighted average remaining contractual term for option awards granted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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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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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 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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