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Stockholders' Equity - Additional Information (Detail) - USD ($)				1 Months Ended			3 Months Ended
	Mar. 31, 2020	Feb. 14, 2020	Feb. 13, 2020	Feb. 29, 2020	Mar. 31, 2019	Jan. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Apr. 30, 2020	May 31, 2018
Stockholders Equity Note [Line Items]
Common stock repurchases, value							$ 353,720,000
Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares							10,861,000
Common stock repurchases, value							$ 109,000
Share Repurchase Program [Member] | Common Stock [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase	$ 2,000,000,000.0						2,000,000,000.0			$ 2,000,000,000.0
Repurchase of common stock, remaining amount	4,000,000						4,000,000
Share Repurchase Program Two [Member] | Common Stock [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase	3,000,000,000.0			$ 3,000,000,000.0			3,000,000,000.0
Repurchase of common stock, remaining amount	$ 3,000,000,000.0						$ 3,000,000,000.0
Share Repurchase Program [Member] | Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares							11,000,000	0
Stock repurchased, average price per share							$ 32.57
Common stock repurchases, value							$ 354,000,000
Subsequent Event [Member]
Stockholders Equity Note [Line Items]
Dividends declared per share									$ 0.0025
MGP BREIT Venture [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units		3,000,000		3,000,000
Partnership interest		50.10%
MGM Growth Properties LLC [Member]
Stockholders Equity Note [Line Items]
Partnership interest	60.60%	60.30%	61.20%		69.80%	74.60%	60.60%
MGM Growth Properties LLC [Member] | Class A shares [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units		5,000,000	13,000,000			20,000,000
Partnership interest						69.70%
New issuance of shares						20,000,000
Number of forward shares settled		5,000,000	13,000,000
MGM Growth Properties LLC [Member] | Empire City [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units						13,000,000
MGM Growth Properties LLC [Member] | Park MGM [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units					1,000,000

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