LONG-TERM DEBT - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term debt, gross	$ 6,954,295	$ 6,371,852
Less: Unamortized discounts and debt issuance costs, net	(45,020)	(28,042)
Long-term debt	6,909,275	6,343,810
Less: Current portion	(675,000)	0
Long-term debt, net	$ 6,234,275	6,343,810
5.375% MGM China senior notes, due 2024
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.375%
Senior notes	$ 0	750,000
6.75% senior notes, due 2025
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.75%
Senior notes	$ 0	750,000
5.75% senior notes, due 2025
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.75%
Senior notes	$ 675,000	675,000
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	0
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	0
6.5% senior notes, due 2032
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.50%
Senior notes	$ 750,000	0
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	$ 353,743	$ 371,300

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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