Amount of additional grants awarded from another states.

No definition available.

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Namespace Prefix:	mcs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of income tax refund claimed by the entity, after reviewing the provisions of CARES Act.

+ References

No definition available.

+ Details

Name:	mcs_IncomeTaxRefundClaimsCaresAct
Namespace Prefix:	mcs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the percentage of theatres open.

+ References

No definition available.

+ Details

Name:	mcs_PercentageOfTheatresOpen
Namespace Prefix:	mcs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of proceeds from grants received.

+ References

No definition available.

+ Details

Name:	mcs_ProceedsFromGrantsReceived
Namespace Prefix:	mcs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Proceeds from income tax refund claimed by the entity, after reviewing Provisions of the Coronavirus Aid, Relief, and Economic Security Act.

+ References

No definition available.

+ Details

Name:	mcs_ProceedsFromIncomeTaxRefundsProvisionsOfCoronavirusAidReliefAndEconomicSecurityAct
Namespace Prefix:	mcs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_GrantsReceivableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3536-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4297-108586

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Impact of COVID-19 Pandemic (Details) - USD ($)			3 Months Ended	9 Months Ended
Impact of COVID-19 Pandemic (Details) - USD ($)	Apr. 01, 2021	Dec. 31, 2020	Sep. 30, 2021	Sep. 30, 2021
Impact of COVID-19 Pandemic
Grants receivable		$ 4,913,000
Percentage of theatres open		52.00%		97.00%
Proceeds from tax refunds				$ 5,900,000
Grants received				8,197,000
Additional theatre grants applied for				4,600,000
Income tax refund claims filled	$ 24,200,000			$ 24,200,000
Proceeds from income tax refunds			$ 1,800,000