LONG-TERM DEBT - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Long-term debt, gross	$ 6,452,585	$ 6,403,119
Less: Unamortized discounts and debt issuance costs, net	(37,957)	(41,021)
Long-term debt	$ 6,414,628	6,362,098
5.25% MGM China senior notes, due 2025
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.25%
Senior notes	$ 500,000	500,000
5.875% MGM China senior notes, due 2026
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.875%
Senior notes	$ 750,000	750,000
4.625% senior notes, due 2026
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	4.625%
Senior notes	$ 400,000	400,000
5.5% senior notes, due 2027
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.50%
Senior notes	$ 675,000	675,000
4.75% MGM China senior notes, due 2027
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	4.75%
Senior notes	$ 750,000	750,000
4.75% senior notes, due 2028
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	4.75%
Senior notes	$ 750,000	750,000
6.125% senior notes, due 2029
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.125%
Senior notes	$ 850,000	850,000
7.125% MGM China senior notes, due 2031
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	7.125%
Senior notes	$ 500,000	500,000
6.5% senior notes, due 2032
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.50%
Senior notes	$ 750,000	750,000
7% debentures, due 2036
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	7.00%
Senior notes	$ 552	552
MGM China first revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 527,033	$ 477,567

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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