COMMITMENTS AND CONTINGENCIES - Joint Venture Put and Call Options and Legal (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Legal
Litigation settlement expense		$ 2.8
Moelis Australia Holdings
Joint venture put and call options
Percentage of purchase price to be paid immediately if the Parent is public and the put option is exercised	50.00%
Period within which the remaining balance is to be paid if the parent is public and the put option is exercised	18 months

Represents the percentage of purchase price to be paid immediately if the parent is public and the put option is exercised.

No definition available.

+ Details

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Namespace Prefix:	mc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the period within which the remaining balance is to be paid if the parent is public and the put option is exercised.

+ References

No definition available.

+ Details

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Namespace Prefix:	mc_
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Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- 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.

+ Details

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- Details

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