GOODWILL AND OTHER INTANGIBLE ASSETS - Schedule of Changes in Company's Goodwill by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 5,145,004	$ 5,165,694
Acquisitions	0	215
Impairment	(278,927)	0	$ 0
Reclassifications	(17,915)	0
Currency exchange	53,798	(20,905)
Goodwill, ending balance	4,901,960	5,145,004	5,165,694
Reportable segments \| Las Vegas Strip Resorts
Goodwill [Roll Forward]
Goodwill, beginning balance	2,707,009	2,707,009
Acquisitions	0	0
Impairment	0	0
Reclassifications	0	0
Currency exchange	0	0
Goodwill, ending balance	2,707,009	2,707,009	2,707,009
Reportable segments \| Regional Operations
Goodwill [Roll Forward]
Goodwill, beginning balance	660,940	660,940
Acquisitions	0	0
Impairment	(256,133)	0
Reclassifications	(17,915)	0
Currency exchange	0	0
Goodwill, ending balance	386,892	660,940	660,940
Reportable segments \| MGM China
Goodwill [Roll Forward]
Goodwill, beginning balance	1,356,625	1,349,356
Acquisitions	0	0
Impairment	0	0
Reclassifications	0	0
Currency exchange	(2,510)	7,269
Goodwill, ending balance	1,354,115	1,356,625	1,349,356
Reportable segments \| MGM Digital
Goodwill [Roll Forward]
Goodwill, beginning balance	420,430	448,389
Acquisitions	0	215
Impairment	(22,794)	0
Reclassifications	0	0
Currency exchange	56,308	(28,174)
Goodwill, ending balance	$ 453,944	$ 420,430	$ 448,389

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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