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Organization - Additional Information (Detail) $ in Thousands, shares in Millions				1 Months Ended			3 Months Ended
	Mar. 31, 2020 USD ($)	Feb. 14, 2020 USD ($) shares	Feb. 13, 2020 shares	Feb. 29, 2020 shares	Mar. 31, 2019	Jan. 31, 2019 shares	Mar. 31, 2020 USD ($) Segment	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Organization Disclosure [Line Items]
Percentage of minority interest	39.40%						39.40%
Debt carrying amount	$ 11,815,242						$ 11,815,242		$ 11,271,706
Payment for purchase of common shares							353,720	$ 0
Revenues							2,252,817	3,176,911
Gain on sales of real estate assets							$ 1,491,945	$ 0
Number of reportable segments \| Segment							3
CityCenter Holdings LLC As Investee [Member]
Organization Disclosure [Line Items]
Percentage ownership interest	50.00%						50.00%		50.00%
Infinity World Development Corp [Member] \| CityCenter Holdings LLC As Investee [Member]
Organization Disclosure [Line Items]
Percentage ownership interest	50.00%						50.00%
Bellagio BREIT Venture [Member]
Organization Disclosure [Line Items]
Percentage of minority interest	5.00%						5.00%
MGP BREIT Venture [Member]
Organization Disclosure [Line Items]
Partnership interest		50.10%
Percentage of minority interest		49.90%
Total consideration received from sale of real estate assets		$ 4,600,000
Cash received from sale of real estate assets		$ 2,500,000
Operating partnership equity interest		50.10%
Issuance of operating partnership units \| shares		3		3
Percentage of issuance of operating partnership units to equity value of consolidated subsidiary		5.00%
Reduction in lease annual rent due to modification		$ 133,000
MGP BREIT Venture [Member] \| Term Loan B [Member]
Organization Disclosure [Line Items]
Debt carrying amount		$ 1,300,000
Blackstone Real Estate Income Trust [Member] \| Class A Shareholders [Member]
Organization Disclosure [Line Items]
Ordinary shares acquired \| shares		5
Payment for purchase of common shares		$ 150,000
MGM Grand Las Vegas [Member]
Organization Disclosure [Line Items]
Revenues		2,500,000
Carrying value of real estate assets		733,000
Selling cost of real estate assets		27,000
Gain on sales of real estate assets		1,700,000
Mandalay Bay [Member]
Organization Disclosure [Line Items]
Revenues		2,100,000
Carrying value of real estate assets		2,300,000
Selling cost of real estate assets		11,000
Gain on sales of real estate assets		$ 252,000
Subsidiary of Blackstone Real Estate Income Trust [Member] \| Bellagio BREIT Venture [Member]
Organization Disclosure [Line Items]
Percentage of ownership interest							95.00%
Class A shares [Member]
Organization Disclosure [Line Items]
Common stock voting rights							one vote per share
Non-Guarantor MGP Subsidiaries [Member] \| Class B shares [Member]
Organization Disclosure [Line Items]
Common stock voting rights							Class B share, is entitled to an amount of votes representing a majority of the total voting power of MGP’s shares so long as the Company and its controlled affiliates’ (excluding MGP) aggregate beneficial ownership of the combined economic interests in MGP and the Operating Partnership does not fall below 30%.
MGM Growth Properties LLC [Member]
Organization Disclosure [Line Items]
Minimum ownership percentage required for majority voting interest							30.00%
Partnership interest	60.60%	60.30%	61.20%		69.80%	74.60%	60.60%
Redemptions discount percentage		3.00%
MGM Growth Properties LLC [Member] \| Maximum [Member]
Organization Disclosure [Line Items]
Cash proceeds for redemption		$ 1,400,000
MGM Growth Properties LLC [Member] \| Class A shares [Member]
Organization Disclosure [Line Items]
Partnership interest						69.70%
Issuance of operating partnership units \| shares		5	13			20
MGM China [Member]
Organization Disclosure [Line Items]
Percentage ownership interest							56.00%