v2.4.1.9

BUSINESS CHANGES AND DEVELOPMENTS (Details)	3 Months Ended	1 Months Ended
	Mar. 31, 2015	Apr. 30, 2014	Aug. 31, 2014
Maximum
Reorganization and initial public offering
Aggregate number of shares of Class B common stock that may be converted into Class A common stock	20,000mc_MaximumNumberOfSharesWhichMayBeConvertedToPubliclyTradedShares / us-gaap_RangeAxis = us-gaap_MaximumMember
Class A common stock
Reorganization and initial public offering
Number of shares of common stock to be issued upon exchange of a partnership unit	1mc_NumberOfSharesIssuableUponExchangeOfEachUnit / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember	1mc_NumberOfSharesIssuableUponExchangeOfEachUnit / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Class A common stock | IPO
Reorganization and initial public offering
Issuance of common stock (in shares)		7,475,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_IPOMember
Class B common stock
Reorganization and initial public offering
Issuance of common stock (in shares)		36,158,698us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Ratio of subscription price to the initial public offering price of shares of common stock	0.00055mc_RatioOfSubscriptionPriceToInitialPublicOfferingPriceUsedAsBasisForDeterminationOfShareholderEconomicRights / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Dividends payable ratio to outstanding shares of publicly traded common stock	0.00055mc_DividendsPayableRatioToOutstandingSharesOfPubliclyTradedCommonStock / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Number of votes entitled to holder for each share of common stock held upon satisfaction of Class B Condition		10mc_NumberOfVotesEntitledToHolderForEachShareOfCommonStockHeldUponSatisfactionOfSpecifiedCondition / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Number of votes entitled to holder for each share of common stock held upon failure of Class B Condition		1mc_NumberOfVotesEntitledToHolderForEachShareOfCommonStockHeldUponFailureOfSpecifiedCondition / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Class B common stock | Maximum
Reorganization and initial public offering
Aggregate number of shares of Class B common stock that may be converted into Class A common stock	20,000mc_MaximumNumberOfSharesWhichMayBeConvertedToPubliclyTradedShares / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Moelis Brazil
Reorganization and initial public offering
Ownership percentage (as a percent)			94.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = mc_MoelisAndCompanyAssessoriaFinanceriaLTDMember
Moelis Brazil | Senior bankers
Reorganization and initial public offering
Ownership percentage (as a percent)			6.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = mc_MoelisAndCompanyAssessoriaFinanceriaLTDMember / us-gaap_TitleOfIndividualAxis = mc_SeniorBankersMember
Group LP
Reorganization and initial public offering
Number of principal classes of units		1mc_NumberOfPrincipalClassesOfUnits / dei_LegalEntityAxis = mc_MoelisAndCompanyGroupLPMember

X

- Definition

Represents the dividends payable ratio to outstanding shares of publicly traded common stock.

+ References

No definition available.

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- Definition

Maximum number of shares that may be converted into publicly traded shares.

+ References

No definition available.

+ Details

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- Definition

Represents the number of principal classes of units.

+ References

No definition available.

+ Details

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Namespace Prefix:	mc_
Data Type:	xbrli:sharesItemType
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X

- Definition

Represents the number of shares to be issued upon exchange of each unit.

+ References

No definition available.

+ Details

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X

- Definition

Represents the number of votes entitled to holder for each share of common stock held of record on all matters submitted to a vote of stockholders, upon failure of a specified condition.

+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

+ Details

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X

- Definition

Represents the ratio of subscription price to the initial public offering price of shares of common stock which is used as basis to determine economic rights of shareholders.

+ References

No definition available.

+ Details

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X

- Details

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X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Period Type:	instant

X

- Definition

Number of new stock issued during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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X

- Details

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