VARIABLE INTEREST ENTITIES - Additional Information (Details) - Consolidated VIEs $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) entity	Dec. 31, 2018 entity
Variable Interest Entity [Line Items]
Number of VIE's consolidated (in entity)	19	23
Consolidated VIEs representing funds and CLOs, assets \| $	$ 7,300.0
Consolidated VIEs representing funds and CLOs, liabilities \| $	5,600.0
Maximum exposure to loss \| $	$ 513.5
Number of fund managed by Oaktree
Variable Interest Entity [Line Items]
Number of VIE's consolidated (in entity)	8
Number of CLO's for which Oaktree acts as collateral manager
Variable Interest Entity [Line Items]
Number of VIE's consolidated (in entity)	10
Number of consolidated funds formed to satisfy risk retention requirements
Variable Interest Entity [Line Items]
Number of VIE's consolidated (in entity)	2
Number of remaining variable interest entities
Variable Interest Entity [Line Items]
Number of VIE's consolidated (in entity)	18

Number of Variable Interest Entities that are Consolidated

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5710-111685

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

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- Definition

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.

+ References

No definition available.

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