DEBT OBLIGATIONS AND CREDIT FACILITIES - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	$ 738,550	$ 483,956
Securities owned and pledged as collateral	$ 3,700,000	3,400,000
Consolidated Funds \| Senior Notes
Debt Instrument [Line Items]
Term (in years)	10 years
Consolidated Funds \| Credit Agreement
Debt Instrument [Line Items]
Borrowings under credit facilities	$ 742,998	488,997
Level III \| Oaktree Capital Group Excluding Consolidated Funds
Debt Instrument [Line Items]
Total CLO debt obligations	$ 787,600	$ 756,600
Average borrowing rate	3.30%	3.90%
Percentage increase in average borrowing rate assumption that would decrease fair value of debt obligation	10.00%
Fair value of debt obligation decrease in value due to increase in average borrowing rate	$ 772,900
Percentage decrease in average borrowing rate assumption that would increase fair value of debt obligation	10.00%
Fair value of debt obligation increase in value due to decrease in average borrowing rate	$ 802,800

Fair value of debt obligation, decrease in value due to increase in average borrowing rate.

No definition available.

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- Definition

Fair value of debt obligation, increase in value due to decrease in average borrowing rate.

+ References

No definition available.

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- Definition

Percentage decrease in average borrowing rate assumption that would increase fair value of debt obligation.

+ References

No definition available.

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- Definition

Percentage increase in average borrowing rate assumption that would lower fair value of debt obligation.

+ References

No definition available.

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- Definition

Senior Notes, Term

+ References

No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

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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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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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-Publisher FASB
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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