v2.4.1.9

EQUITY-BASED COMPENSATION (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Apr. 30, 2014
Class A common stock
Equity-based compensation
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 | Share repurchase program authorized first quarter 2015
Equity-based compensation
Share value authorized for repurchase	$ 25,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_ShareRepurchaseProgramAxis = mc_ShareRepurchaseProgramAuthorizedFirstQuarter2015Member / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Partnership units
Equity-based compensation
Units held by partners	34,479,961us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber / us-gaap_AwardTypeAxis = mc_PartnershipUnitsMember
Unvested units held by partners	719,720us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mc_PartnershipUnitsMember
Compensation expenses	1,066,000us-gaap_AllocatedShareBasedCompensationExpense / us-gaap_AwardTypeAxis = mc_PartnershipUnitsMember	11,010,000us-gaap_AllocatedShareBasedCompensationExpense / us-gaap_AwardTypeAxis = mc_PartnershipUnitsMember
Unrecognized compensation expenses	$ 8,402,000us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized / us-gaap_AwardTypeAxis = mc_PartnershipUnitsMember
Weighted average period to recognize unrecognized compensation expense	2 years 6 months
Managing Directors | Partnership units | Minimum
Equity-based compensation
Vesting period	5 years
Managing Directors | Partnership units | Maximum
Equity-based compensation
Vesting period	8 years
Non-managing director employees | Partnership units
Equity-based compensation
Vesting period	4 years

X

- Definition

Represents the amount of unrecognized cost of unvested share-based compensation awards to be amortized over relevant vesting period after initial public offering of shares.

+ References

No definition available.

+ Details

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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 expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 1

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-Publisher FASB

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-Topic 718

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-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901



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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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X

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(1)

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X

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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X

- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901



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-Publisher FASB

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-Topic 718

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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X

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Details

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X

- Details

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X

- Details

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