Fixed annual rent escalator percentage.

No definition available.

Name:	mgm_FixedAnnualRentEscalatorPercentage
Namespace Prefix:	mgm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

+ Details

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

- Definition

The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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

No definition available.

+ Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions		1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 01, 2021	Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2021	Mar. 15, 2021
Related Party Transaction [Line Items]
Cash proceeds for redemption			$ 50,828
Real Estate Assets and Leases [Member] \| Blackstone Real Estate Income Trust [Member] \| Bellagio BREIT Venture [Member]
Related Party Transaction [Line Items]
Ownership interest		5.00%	5.00%	5.00%
MGP [Member] \| Blackstone Real Estate Income Trust [Member] \| Lease Agreements [Member]
Related Party Transaction [Line Items]
Ownership interest		50.10%	50.10%	50.10%
MGM Growth Properties LLC [Member] \| Operating Partnership [Member]
Related Party Transaction [Line Items]
Operating partnership units, redeemed		37
Cash proceeds for redemption		$ 1,200,000
Ownership interest		42.10%	42.10%	42.10%	42.10%
Master Lease [Member]
Related Party Transaction [Line Items]
Annual rent payments under master lease of properties				$ 828,000
Master Lease [Member] \| Subsequent Event [Member]
Related Party Transaction [Line Items]
Annual rent payments under master lease of properties	$ 843,000
Fixed annual rent escalator percentage	2.00%