STOCK-BASED COMPENSATION PLANS - Stock option activity (Details) - USD ($)	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Feb. 29, 2012
Stock Based Compensation [Line Items]
Granted, Number of Shares	160,000
Vested and Expected to vest, Number of Shares				90,000
Equity Option [Member]
Stock Based Compensation [Line Items]
Outstanding, Number of Shares	368,000	368,000
Exercised, Number of Shares	(26,805)
Outstanding, Number of Shares	341,195	368,000	368,000
Exercisable, Number of Shares	330,395	318,000
Vested and Expected to vest, Number of Shares	341,195	368,000
Outstanding, Weighted Average Exercise Price	$ 17.21	$ 17.21
Exercised, Weighted Average Exercise Price	20.52
Outstanding, Weighted Average Exercise Price	16.95	17.21	$ 17.21
Exercisable, Weighted Average Exercise Price	16.62	16.47
Vested and Expected to vest, Weighted Average Exercise Price	$ 16.95	$ 17.21
Outstanding at Weighted Average Remaining Life	3 years 26 days	4 years 2 months 1 day	5 years 2 months 1 day
Exercisable, Weighted Average Remaining Life	2 years 11 months 1 day	3 years 9 months 15 days
Vested and Expected to vest, Weighted Average Remaining Life	3 years 26 days	4 years 2 months 1 day
Outstanding, Aggregate Intrinsic Value	$ 4,680,000	$ 3,505,000	$ 3,046,000
Exercisable, Aggregate Intrinsic Value	4,643,000	3,257,000
Vested and Expected to vest, Aggregate Intrinsic Value	$ 4,680,000	$ 3,505,000

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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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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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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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