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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 ($) $ / shares in Units, shares in Thousands			1 Months Ended				3 Months Ended			6 Months Ended
	Aug. 07, 2019	Jul. 26, 2019	Jun. 30, 2019	Apr. 30, 2019	Mar. 31, 2019	Jan. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	May 31, 2018	Sep. 30, 2017
Stockholders Equity Note [Line Items]
Common stock repurchases, value							$ 281,833,000	$ 594,864,000	$ 362,400,000
Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares							11,005	19,004	10,000
Common stock repurchases, value							$ 110,000	$ 190,000	$ 100,000
Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase												$ 2,000,000,000.0
Repurchase of common stock, remaining amount			$ 1,100,000,000				$ 1,100,000,000			$ 1,100,000,000
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							11,000	19,000		11,000	29,000
Average price per share							$ 25.61	$ 31.30		$ 25.61	$ 33.00
Common stock repurchases, value							$ 282,000,000	$ 595,000,000		$ 282,000,000	$ 957,000,000
Subsequent Event [Member]
Stockholders Equity Note [Line Items]
Dividend declared date		Jul. 25, 2019
Dividend paid date		Sep. 16, 2019
Dividend record date		Sep. 10, 2019
Dividends declared per share		$ 0.13
Subsequent Event [Member] \| Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares	6,000
Average price per share	$ 28.86
Common stock repurchases, value	$ 173,000,000
Class A shares [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units						20,000
Partnership interest						69.70%
New issuance of shares						20,000
MGM Growth Properties LLC [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units				9,000	1,000
Partnership interest			68.30%	68.80%	69.80%	74.60%
MGM Growth Properties LLC [Member] \| Class A shares [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units							2,000
Partnership interest							68.30%
New issuance of shares							2,000
MGM Growth Properties LLC [Member] \| Empire City [Member]
Stockholders Equity Note [Line Items]
Issuance of operating partnership units						13,000