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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 |  |  |  |  |  |

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