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Represents the amount of fee paid for certain services resulting from transactions with related party.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of interest income earned from interest-bearing assets owed to the entity by related party.

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Dividends received on equity and other investments during the current period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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The cash inflow from a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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RELATED-PARTY TRANSACTIONS (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
RELATED-PARTY TRANSACTIONS (Details) $ in Thousands	Aug. 30, 2014 item	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2014 USD ($)
Related-party transactions
Investment into the entity controlled by a related party		$ 20,309		$ 20,309		$ 17,459
Income (loss) from equity method investments		1,562	$ 450	3,897	$ 3,510
Manager \| Aircraft lease entered into during August 2014
Related-party transactions
Expenses		312	312	936	936
Number of other lessees \| item	2
Employees \| Unsecured promissory notes
Related-party transactions
Unsecured promissory notes from employees		937		$ 937		$ 119
Interest rates (as a percent)				4.00%		4.00%
Principal repayments				$ 0	0
Interest income recognized				15	4
Moelis Australia Holdings
Related-party transactions
Due from related party		1,035		1,035
Due to related party						$ 167
Income (loss) from equity method investments		1,571	163	2,176	442
Moelis Asset Management LP
Related-party transactions
Fee for services		285	420	996	1,265
Due from related party		0		0		$ 3
Investment into the entity controlled by a related party							$ 265
Income (loss) from equity method investments		(9)	287	1,721	3,068
Cash distributions				813	2,694
Revenue from related parties		$ 170	$ 1,299	$ 7,186	$ 5,635