ORGANIZATION (Details)	6 Months Ended
Jun. 30, 2025 resort segment
Organization Disclosure [Line Items]
Number of reportable segments \| segment	4
BetMGM LLC
Organization Disclosure [Line Items]
Ownership interest (as a percent)	50.00%
BetMGM LLC \| Entain plc
Organization Disclosure [Line Items]
Ownership interest (as a percent)	50.00%
MGM Osaka \| Japan
Organization Disclosure [Line Items]
Ownership interest (as a percent)	50.00%
MGM China
Organization Disclosure [Line Items]
Controlling interest (as a percent)	56.00%
Number of integrated casino \| resort	2

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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-Topic 280
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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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