EARNINGS PER UNIT - Computations of Net Income (Loss) Per Unit (Additional Information) (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2017 shares	Sep. 30, 2017 shares
Highstar Capital
Earnings Per Share [Line Items]
Performance period (in years)		7 years
Deferred Equity Units
Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	0	0
Deferred Equity Units
Earnings Per Share [Line Items]
Vesting period		4 years
OCGH Units
Earnings Per Share [Line Items]
Exchange ratio		1
OCGH Issued (in shares)	91,682,408	91,682,408
Class A Units
Earnings Per Share [Line Items]
Exchange ratio		1
Antidilutive securities excluded from earnings per share computation (in shares)		91,682,408

Antidilutive Securities Excluded From Computation, Share Exchange Ratio

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Section 50
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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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