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Percent interest in a less than hundred percent owned consolidated affiliate.

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Stockholders equity note.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Number of new stock issued during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Stockholders' Equity - Additional Information (Detail) - USD ($)		1 Months Ended			3 Months Ended
	Apr. 29, 2019	Apr. 30, 2019	Mar. 31, 2019	Jan. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2018	May 31, 2018	Sep. 30, 2017
Stockholders Equity Note [Line Items]
Repurchase of common stock							$ 362,400,000
Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares							10,000,000
Repurchase of common stock							$ 100,000
Share Repurchase Program [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase								$ 2,000,000,000.0
Repurchase of common stock, remaining amount			$ 1,400,000,000			$ 1,400,000,000
Share Repurchase Program Two [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase									$ 1,000,000,000.0
Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares						0	10,000,000
Stock repurchased, average price per share							$ 36.24
Repurchase of common stock							$ 362,000,000
Subsequent Event [Member]
Stockholders Equity Note [Line Items]
Dividend declared date	Apr. 29, 2019
Dividend paid date	Jun. 14, 2019
Dividend record date	Jun. 10, 2019
Dividends declared per share	$ 0.13
MGM Growth Properties LLC [Member]
Stockholders Equity Note [Line Items]
Partnership interest			69.80%	74.60%		69.80%
MGM Growth Properties LLC [Member] \| Forecast [Member]
Stockholders Equity Note [Line Items]
Partnership interest					68.80%
MGM Growth Properties LLC [Member] \| Subsequent Event [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units		9,000,000
MGM Growth Properties LLC [Member] \| Class A shares [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units				20,000,000
Partnership interest				69.70%
New issuance of shares				20,000,000
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