Stock Based Compensation (Schedule of Stock Option Activity) (Details) - USD ($)	6 Months Ended	12 Months Ended
Dec. 31, 2017	Jun. 30, 2017
Number of Shares Subject To Options
Balance at July 1, 2017	197,800
Granted	51,515
Exercised
Forfeited or expired	(1,250)
Outstanding at December 31, 2017	248,065	197,800
Vested or expected to vest at December 31, 2017	233,886
Exercisable at December 31, 2017	154,650
Weighted Average Exercise Price
Balance at July 1, 2017	$ 24.57
Granted	21.75
Exercised
Forfeited or expired	26.00
Outstanding at December 31, 2017	23.98	$ 24.57
Vested or expected to vest at December 31, 2017	23.99
Exercisable at December 31, 2017	$ 24.13
Weighted Average Remaining Contractual Term
Outstanding	6 years 3 months 11 days	5 years 10 months 10 days
Granted	9 years 9 months 22 days
Vested or expected to vest at December 31, 2017	6 years 1 month 2 days
Exercisable at December 31, 2017	4 years 4 months 24 days
Aggregate Intrinsic Value
Outstanding at December 31, 2017	$ 309,072
Vested or expected to vest at December 31, 2017	291,851
Exercisable at December 31, 2017	$ 195,224

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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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Weighted average price of options that were either forfeited or expired.

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Net 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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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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