Annual rent escalator after year ten.

No definition available.

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- Definition

Annual rent escalator cap after year ten.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

Annual Rent Escalator From Year One Through Year Fifteen

+ References

No definition available.

+ Details

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Namespace Prefix:	mgm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Annual Rent Escalator From Year One Through Year Ten

+ References

No definition available.

+ Details

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Namespace Prefix:	mgm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Decrease in annual rent payment.

+ References

No definition available.

+ Details

Name:	mgm_DisposalGroupDecreaseInAnnualRentPayment
Namespace Prefix:	mgm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Disposal Group, Master Lease, Decrease In Annual Rent Payment

+ References

No definition available.

+ Details

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Namespace Prefix:	mgm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Lease Agreement Renewal Period

+ References

No definition available.

+ Details

Name:	mgm_LeaseAgreementRenewalPeriod
Namespace Prefix:	mgm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Lease Liabilities Derecognized Upon Lease Modification

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Lessee, Operating Lease, Annual Rent Expense

+ References

No definition available.

+ Details

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

- Definition

Lessee, Operating Lease, Right Of Use Assets Derecognized Upon Lease Modification

+ References

No definition available.

+ Details

Name:	mgm_LesseeOperatingLeaseRightOfUseAssetsDerecognizedUponLeaseModification
Namespace Prefix:	mgm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of renewal periods, exercisable at option.

+ References

No definition available.

+ Details

Name:	mgm_NumberOfRenewalPeriodsExercisableAtOption
Namespace Prefix:	mgm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) on termination of lease before expiration of lease term.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479092/842-20-40-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	mgm_LeaseAxis=mgm_VICILeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Period Type:

LEASES - Additional Information (Details) - VICI lease $ in Millions			1 Months Ended	9 Months Ended
	May 01, 2026 USD ($)	Apr. 29, 2022 vote	Apr. 30, 2026 USD ($)	Sep. 30, 2026 USD ($)
Lessee, Lease, Description [Line Items]
Lease agreement initial lease term		25 years
Number of renewal periods, exercisable at option \| vote		3
Lessor, operating lease, renewal term		10 years
Annual rent escalator from year one through year ten		2.00%
Lease agreement renewal period		10 years
Annual rent escalator after year ten		2.00%
Annual rent escalator cap after year ten		3.00%
Lessee, operating lease, annual rent expense	$ 736
Annual rent escalator from year one through year fifteen	2.00%
Disposal group, disposed of by sale, not discontinued operations \| MGM Northfield Park
Lessee, Lease, Description [Line Items]
Decrease in annual rent payment under master lease			$ 53
Decrease in annual rent payment			722
Right-of-use assets derecognized upon lease modification			1,100
Lease liabilities derecognized upon lease modification			1,200
Gain on partial lease termination			$ 51	$ 51