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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended			12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 26, 2022	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2021
Income Tax Disclosure [Line Items]
Effective income tax rate provision (benefit)	17.40%	(11.30%)		16.90%		(8.90%)
Income tax expense	$ 282,135,000	$ (76,734,000)		$ 222,263,000		$ (84,668,000)
Cash tax payments				0
Macau Taxing Authority
Income Tax Disclosure [Line Items]
Decrease in foreign tax credit carry forward valuation allowance	10,000,000			$ 5,000,000
Special gaming tax rate				35.00%
Income tax expense	$ 3,000,000			$ 3,000,000	$ 1,000,000
Marina District Development Company, LLC
Income Tax Disclosure [Line Items]
Unrecognized tax benefits reversed				$ 30,000,000
MGM Grand Paradise SA \| Macau Taxing Authority
Income Tax Disclosure [Line Items]
Complementary tax rate on distributions of gaming profits				12.00%
Annual fee payments					$ 1,000,000
MGM Grand Paradise SA \| Scenario Forecast \| Macau Taxing Authority
Income Tax Disclosure [Line Items]
Annual fee payments			$ 1,000,000				$ 2,000,000