Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, Gross	$ 15,066,825	$ 15,253,239
Less: Premiums, discounts, and unamortized debt issuance costs, net	(122,951)	(121,823)
Long-term debt	14,943,874	15,131,416
Less: Current portion	0	(43,411)
Long-term debt, net	14,943,874	15,088,005
Senior Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, Gross	1,260,000	750,000
Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, Gross	2,252,313	2,819,125
MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, Gross	775,658	2,433,562
Less: Current portion		(43,000)
8.625% senior notes, due 2019 [Member]
Debt Instrument [Line Items]
Senior notes	0	850,000
5.25% senior notes, due 2020 [Member]
Debt Instrument [Line Items]
Senior notes	267,476	500,000
6.75% senior notes, due 2020 [Member]
Debt Instrument [Line Items]
Senior notes	360,826	1,000,000
6.625% senior notes, due 2021 [Member]
Debt Instrument [Line Items]
Senior notes	1,250,000	1,250,000
7.75% senior notes, due 2022 [Member]
Debt Instrument [Line Items]
Senior notes	1,000,000	1,000,000
6% senior notes, due 2023 [Member]
Debt Instrument [Line Items]
Senior notes	1,250,000	1,250,000
5.625% Operating Partnership senior notes, due 2024 [Member]
Debt Instrument [Line Items]
Senior notes	1,050,000	1,050,000
5.375% MGM China senior notes, due 2024 [Member]
Debt Instrument [Line Items]
Senior notes	750,000	0
5.75% senior notes, due 2025 [Member]
Debt Instrument [Line Items]
Senior notes	1,000,000	1,000,000
5.875% MGM China senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Senior notes	750,000	0
4.5% Operating Partnership senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Senior notes	500,000	500,000
4.625% senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Senior notes	500,000	500,000
5.75% Operating Partnership senior notes, due 2027 [Member]
Debt Instrument [Line Items]
Senior notes	750,000	0
5.5% senior notes, due 2027 [Member]
Debt Instrument [Line Items]
Senior notes	1,000,000	0
4.5% Operating Partnership senior notes, due 2028 [Member]
Debt Instrument [Line Items]
Senior notes	350,000	350,000
7% debentures, due 2036 [Member]
Debt Instrument [Line Items]
Senior notes	$ 552	$ 552

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

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

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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 after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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