v2.4.1.9

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Deferred Tax Asset and Amount Due Pursuant to Tax Receivable Agreement
Percentage of tax benefits payable to partners under tax receivable agreement	85.00%mc_TaxReceivableAgreementPaymentPercentageOfCashSavingsRealizedToEligibleManagingDirectors
Remaining percentage of cash savings realized by the Company (as a percent)	15.00%mc_TaxReceivableAgreementPaymentPercentageOfCashSavingsRealizedByReportingEntity
Revenue and Expense Recognition
Reimbursable expenses billed to clients	$ 2,873us-gaap_ReimbursementRevenue	$ 2,510us-gaap_ReimbursementRevenue
Equity-based Compensation
Minimum age of retiring employees required so that certain qualifying awards granted during employment will not be forfeited	54 years
Consecutive years of service of retiring employees required so that certain qualifying awards granted during employment will not be forfeited	8 years
Income Taxes
Unrecognized Tax Benefits	0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits, interest and penalties	$ 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	$ 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense
Office Equipment And Furniture And Fixtures | Maximum
Equipment and leasehold improvements
Useful lives	7 years
Office Equipment And Furniture And Fixtures | Minimum
Equipment and leasehold improvements
Useful lives	3 years

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- Definition

Minimum age of retiring employees required so that certain qualifying awards granted during employment will not be forfeited, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Consecutive years of service of retiring employees required so that certain qualifying awards granted during employment will not be forfeited, in PnYnMnDTnHnMnS' format, for example,

+ References

No definition available.

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- Definition

Represents the remaining percentage of cash savings realized by the reporting entity under the tax receivable agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the payment percentage of cash savings payable to eligible managing directors for any amounts realized under tax receivable agreement.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 45

-Section 45

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21915142&loc=d3e60722-111653

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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