DEBT OBLIGATIONS AND CREDIT FACILITIES - Debt Obligations (Details) - USD ($)	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Less: Debt issuance costs	$ (8,227,000)	$ (5,041,000)
Debt obligations	861,871,000	483,956,000
Oaktree Capital Group Excluding Consolidated Funds
Debt Instrument [Line Items]
Total remaining principal	750,000,000	750,000,000
Less: Debt issuance costs	(3,444,000)	(4,103,000)
Debt obligations	746,556,000	745,897,000
Oaktree Capital Group Excluding Consolidated Funds \| Senior secured notes \| $250,000, 6.75%, issued in November 2009, payable on December 2, 2019
Debt Instrument [Line Items]
Total remaining principal	250,000,000	250,000,000
Face amount	$ 250,000,000
Stated percentage	6.75%
Oaktree Capital Group Excluding Consolidated Funds \| Senior secured notes \| $50,000, 3.91%, issued in September 2014, payable on September 3, 2024
Debt Instrument [Line Items]
Total remaining principal	$ 50,000,000	50,000,000
Face amount	$ 50,000,000
Stated percentage	3.91%
Oaktree Capital Group Excluding Consolidated Funds \| Senior secured notes \| $100,000, 4.01%, issued in September 2014, payable on September 3, 2026
Debt Instrument [Line Items]
Total remaining principal	$ 100,000,000	100,000,000
Face amount	$ 100,000,000
Stated percentage	4.01%
Oaktree Capital Group Excluding Consolidated Funds \| Senior secured notes \| $100,000, 4.21%, issued in September 2014, payable on September 3, 2029
Debt Instrument [Line Items]
Total remaining principal	$ 100,000,000	100,000,000
Face amount	$ 100,000,000
Stated percentage	4.21%
Oaktree Capital Group Excluding Consolidated Funds \| Senior secured notes \| $100,000, 3.69%, issued in July 2016, payable on July 12, 2031
Debt Instrument [Line Items]
Total remaining principal	$ 100,000,000	100,000,000
Face amount	$ 100,000,000
Stated percentage	3.69%
Oaktree Capital Group Excluding Consolidated Funds \| Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Total remaining principal	$ 150,000,000	$ 150,000,000
Face amount	250,000,000
Oaktree Capital Group Excluding Consolidated Funds \| Credit Agreement \| Revolving credit facility
Debt Instrument [Line Items]
Credit facility	$ 500,000,000
Unused commitment fee	0.125%
Borrowings under credit facilities	$ 0
Oaktree Capital Group Excluding Consolidated Funds \| Credit Agreement \| Revolving credit facility \| LIBOR
Debt Instrument [Line Items]
LIBOR margin	1.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

+ References

No definition available.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-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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