Name:	mcri_ConsolidatedLeverageRatio
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to interest expense, which is necessary to be maintained under the terms of the credit facilities' covenants.

No definition available.

Name:	mcri_DebtInstrumentCovenantConsolidatedLeverageRatio
Namespace Prefix:	mcri_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the ratio of earnings-before-interest-taxes-depreciation and amortization (EBITDA) to fixed charges allowed under the terms of the covenants of the credit facility.

No definition available.

Name:	mcri_DebtInstrumentCovenantFixedChargeCoverageRatio
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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to fixed charges.

No definition available.

Name:	mcri_FixedChargeCoverageRatio
Namespace Prefix:	mcri_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The contingent decrease to the maximum borrowing capacity under the credit facility in the period following a milestone achievement or event, as defined in the credit facility agreement.

No definition available.

Name:	mcri_LineOfCreditFacilityContingentDecreaseReductionToBorrowingCapacity
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of decrease of the credit facility from mandatory reductions pursuant to the agreement.

No definition available.

Name:	mcri_LineOfCreditFacilityMandatoryReductionInBorrowingCapacity
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents the amount in which the maximum borrowing capacity under the credit facility was permanently reduced.

No definition available.

Name:	mcri_LineOfCreditFacilityPermanentReductionAmountInMaximumBorrowingFacility
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the required multiple which may be used to permanently reduce the maximum borrowing capacity under the credit facility.

No definition available.

Name:	mcri_LineOfCreditFacilityPermanentReductionAmountInMaximumBorrowingFacilityMultiple
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the amount of outstanding borrowings under a line of credit the will contingently convert to a term loan in the period following a milestone achievement or event, as defined in the credit facility agreement.

No definition available.

Name:	mcri_LineOfCreditFacilityRevolvingCreditContingentConversionToTermLoan
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of decrease of the credit facility from voluntary reductions as allowed under the agreement.

No definition available.

Name:	mcri_LineOfCreditFacilityVoluntaryReductionInBorrowingCapacity
Namespace Prefix:	mcri_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

Name:	us-gaap_LongTermDebtPercentageBearingVariableInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Name:	us-gaap_DebtInstrumentAxis=mcri_AmendedAndRestatedCreditFacilityAgreement20July2016Member
Namespace Prefix:
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Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_StatementScenarioAxis=mcri_CompletionOfExpansionProjectAtMonarchCasinoBlackHawkMember
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Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=mcri_AmendedAndRestatedCreditFacilityAgreement15November2011Member
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
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