EQUITY-BASED COMPENSATION - Deferred Equity Units (Details) - OCGH Units $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exchange ratio	1
Vesting period	10 years
Nonvested units outstanding (in shares)	847,115,000
Awards expected to vest (in shares)	557,308,000
Unrecognized compensation cost \| $	$ 19.9
Weighted average period of recognition non-vested equity-based awards	7 years 8 months 12 days
Lack-of-marketability discount	17.50%

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Awards Expected to Vest

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Lack of Marketability Discount

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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