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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The profit or loss on sales of previously unissued stock by subsidiaries or equity investees made to investors outside the consolidated group that is not reported as operating income. Represents the difference in the parent company's carrying amount of the equity interest in the subsidiary or equity investee immediately before and after the transaction.

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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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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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

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Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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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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No definition available.

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EQUITY METHOD INVESTMENTS (Details) - USD ($) $ in Thousands						1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 30, 2017	Sep. 13, 2017	Jun. 01, 2017	Apr. 18, 2017	Apr. 10, 2017	Jun. 30, 2014	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Equity Method Investments
Gain recognized by Company on issuance of shares									$ 31,971
Income (loss) from equity method investments							$ 2,791	$ 1,562	4,565	$ 3,897
Return of capital from equity method investments										9
Investment into the entity controlled by a related party							45,734		45,734		$ 20,873
Moelis Australia Holdings
Equity Method Investments
Gain recognized by Company on issuance of shares		$ 14,429	$ 2,372		$ 15,170
Income (loss) from equity method investments					$ (2,400)		$ 2,806	1,571	$ 4,592	2,176
Return of capital from equity method investments				$ 11,672
Shares issued		11,940,000
Moelis Australia Holdings \| Subsequent event
Equity Method Investments
Shares issued	10,060,000
Entity controlled by Moelis Asset Management LP
Equity Method Investments
Income (loss) from equity method investments								$ (9)		1,721
Cash contribution made						$ 265
Investment into the entity controlled by a related party											$ 30
Cash distributions										$ 813