Increase in annual rent payment.

No definition available.

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

- Definition

Percentage of fixed annual rent.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage of increase in annual rent per year.

+ References

No definition available.

+ Details

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Namespace Prefix:	mgm_
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- Definition

Redemption of operating partnership units.

+ References

No definition available.

+ Details

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Namespace Prefix:	mgm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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- 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 distributions of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- 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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- Details

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Related Party Transactions - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions				1 Months Ended		3 Months Ended
	Apr. 01, 2019	Mar. 07, 2019	Jan. 29, 2019	Mar. 31, 2019	Jan. 31, 2019	Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Total purchase price		$ 638
Purchase price in cash		606
Master Lease [Member]
Related Party Transaction [Line Items]
Increase in annual rent payment		$ 50
Annual fixed rent, percentage		90.00%
Increase in annual rent per year, percentage		2.00%
Annual rent payments under master lease of properties	$ 946			$ 870	$ 770
Empire City [Member]
Related Party Transaction [Line Items]
Total purchase price			$ 865
Empire City [Member] \| Developed Real Property [Member]
Related Party Transaction [Line Items]
Total purchase price					634
Liabilities incurred for acquisition					246
Increase in annual rent payment					$ 50
Annual fixed rent, percentage					90.00%
Increase in annual rent per year, percentage					2.00%
Northfield OpCo [Member]
Related Party Transaction [Line Items]
Total purchase price	301
Northfield OpCo [Member] \| Master Lease [Member]
Related Party Transaction [Line Items]
Increase in annual rent payment	$ 60
Annual fixed rent, percentage	90.00%
Increase in annual rent per year, percentage	2.00%
MGM Branding and Development [Member] \| Ms Ho Pansy Catilina Chiu King [Member]
Related Party Transaction [Line Items]
Distribution made to noncontrolling interests						$ 5	$ 10
MGM Growth Properties LLC [Member] \| Northfield OpCo [Member]
Related Party Transaction [Line Items]
Redemption of operating partnership units	9