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Represents the commencing, minimum annual amount for rent under a lease agreement.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents the number of terms for which the lease can be renewed.

No definition available.

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Data Type:	xbrli:integerItemType
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Amount due to related party in the event that the lease is not renewed.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Area of land held.

No definition available.

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Area of a real estate property.

No definition available.

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Indicates (true false) whether lessee has option to extend operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of operating lease expense. Excludes sublease income.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
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Present value of lessee's discounted obligation for lease payments from operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Indicates line item in statement of financial position that includes operating lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147479041/842-20-45-2

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Data Type:	enum2:enumerationSetItemType
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Amount of lessee's right to use underlying asset under operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

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Indicates line item in statement of financial position that includes operating lease right-of-use asset.

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Data Type:	enum2:enumerationSetItemType
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Period Type:	instant

Cash payments to lessor's for use of assets under operating leases.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Paragraph 25
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Name:	us-gaap_PaymentsForRent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=mcri_BiggestLittleInvestmentsLimitedPartnershipMember
Namespace Prefix:
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Name:	us-gaap_RelatedPartyTransactionAxis=mcri_ShoppingCenterSurfaceLotLeaseMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_RelatedPartyTransactionAxis=mcri_ShoppingCenterDrivewayLeaseMember
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Data Type:	na
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
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Name:	us-gaap_RelatedPartyTransactionAxis=mcri_RelatedPartyLeasesForBillboardAdvertisingStorageSpaceAndParkingLotSpaceMember
Namespace Prefix:
Data Type:	na
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Name:	dei_LegalEntityAxis=mcri_GoldenRoadMotorInnInc.Member
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