LONG-TERM DEBT - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt, gross	$ 6,916,126	$ 8,761,189
Less: Premiums, discounts, and unamortized debt issuance costs, net	(38,151)	(41,899)
Long-term debt	6,877,975	8,719,290
Less: Current portion	(36,492)	(1,286,473)
Long-term debt, net	$ 6,841,483	7,432,817
6% senior notes, due 2023
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.00%
Senior notes	$ 0	1,250,000
5.375% MGM China senior notes, due 2024
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	5.375%
Senior notes	$ 750,000	750,000
6.75% senior notes, due 2025
Debt Instrument [Line Items]
Long-term debt, interest rate (in percent)	6.75%
Senior notes	$ 750,000	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
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	879,003	1,249,744
MGM China second revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	0	224,313
LeoVegas senior notes, due 2023
Debt Instrument [Line Items]
Senior notes	$ 36,571	$ 36,580

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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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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