v2.4.1.9

REGULATORY REQUIREMENTS (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Regulatory requirements
Minimum net capital requirement	$ 250us-gaap_AlternativeNetCapitalRequirement1
Moelis US
Regulatory requirements
Net capital	32,769us-gaap_NetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyLLCMember	80,270us-gaap_NetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyLLCMember
Net capital in excess of required net capital	32,519us-gaap_AlternativeExcessNetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyLLCMember	80,020us-gaap_AlternativeExcessNetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyLLCMember
Moelis UK
Regulatory requirements
Net capital	18,923us-gaap_NetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyUKLLPMember	22,980us-gaap_NetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyUKLLPMember
Net capital in excess of required net capital	$ 18,868us-gaap_AlternativeExcessNetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyUKLLPMember	$ 22,919us-gaap_AlternativeExcessNetCapital / dei_LegalEntityAxis = mc_MoelisAndCompanyUKLLPMember

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- Definition

The amount of net capital in excess of the alternative minimum required net capital.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3

-Number 240

-Section 1

-Paragraph 1

-Subparagraph ii

-Article 15c3

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Amount of net capital requirement computed under the alternative method allowed under regulatory reporting requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3

-Number 240

-Section 1

-Paragraph 1

-Subparagraph ii

-Article 15c3

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- Definition

Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3

-Number 240

-Section 1

-Paragraph 1

-Subparagraph ii

-Article 15c3

-Subsection a

+ Details

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