STOCK-BASED COMPENSATION (Summary of Part B RSUs Granted and Units Converted to Common Stock) (Details) - Part B restricted stock units - $ / shares	3 Months Ended	9 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Part B RSUs granted	98,342	61,123	58,418	78,123	77,218	82,556	163,960	217,883
Maximum eligible shares of the Company's common stock	826,073	513,433	403,084	539,049	532,804	569,636	590,256	826,073
Average grant date fair value	$ 52.81	$ 22.43	$ 64.41	$ 74.44	$ 52.47	$ 45.10	$ 19.06	$ 47.40
Units converted to Company's common stock at vesting date							54,671

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Converted to Company Stock

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