DEBT OBLIGATIONS AND CREDIT FACILITIES - Credit Facilities of Consolidated Funds (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Less: Debt issuance costs	$ (4,042)	$ (3,646)
Debt obligations	795,958	846,354
Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	65,700	6,442,742
Debt obligations	2,678,566	2,330,359
Credit facilities \| Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	65,700	2,381,324
Credit agreement	$ 450,000
LIBOR margin (as a percent)	1.25%
Maturity	Apr. 19, 2019
Revolving credit facilities \| Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	$ 0	2,718,394
Senior variable rate notes \| Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	0	1,363,044
Credit Agreement \| Consolidated Funds
Debt Instrument [Line Items]
Borrowings under credit facilities	65,700	6,462,762
Less: Debt issuance costs	0	(20,020)
Debt obligations	65,700	6,442,742
Level III
Debt Instrument [Line Items]
Fair value	$ 812,500	855,300
Level III \| Senior Notes \| Consolidated Funds
Debt Instrument [Line Items]
Fair value		$ 3,700,000

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

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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

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-Publisher FASB
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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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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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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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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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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

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))
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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