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Investments in and Advances to Unconsolidated Affiliates - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2021 | Apr. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Sep. 30, 2021 | Dec. 31, 2020
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Distributions from unconsolidated affiliates |  |  |  |  | $ 803 | $ 63,251 |  |
City Center Holdings L L C [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Distribution paid/declared |  | $ 101,000 |  |  |  |  |  |
MGP BREIT Venture [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Distributions from unconsolidated affiliates |  |  | $ 32,000 | $ 23,000 | $ 47,000 | 35,000 |  |
Percentage ownership interest | 50.10% |  | 50.10% |  | 50.10% |  |  | 50.10%
BetMGM [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Contributions to unconsolidated affiliates |  |  | $ 25,000 | $ 10,000 | $ 100,000 | $ 30,000 |  |
Percentage ownership interest | 50.00% |  | 50.00% |  | 50.00% |  |  | 50.00%
CityCenter Holdings LLC As Investee [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Distributions from unconsolidated affiliates |  | $ 51,000 |  |  |  |  |  |
Percentage ownership interest | 50.00% |  | 50.00% |  | 50.00% |  |  | 50.00%
Distributions from unconsolidated affiliates, percentage |  | 50.00% |  |  |  |  |  |
CityCenter Holdings LLC As Investee [Member] | Scenario Forecast [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Percentage ownership interest |  |  |  |  |  |  | 100.00% |
CityCenter Holdings LLC As Investee [Member] | Infinity World Development Corp [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Percentage ownership interest | 50.00% |  | 50.00% |  | 50.00% |  |  |
Harmon Land [Member] | City Center Holdings L L C [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Consideration received from sale of discontinued operations | $ 80,000 |  | $ 80,000 |  | $ 80,000 |  |  |
Recognized gain on sale, unconsolidated affiliates and reversal of basis differences | 30,000 |  |  |  |  |  |  |
Harmon Land [Member] | CityCenter Holdings LLC As Investee [Member] |  |  |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Distributions from unconsolidated affiliates | $ 15,000 |  |  |  |  |  |  |
Distributions from unconsolidated affiliates, percentage | 50.00% |  |  |  |  |  |  |
Consideration received from sale of discontinued operations | $ 50,000 |  | $ 50,000 |  | $ 50,000 |  |  |
Recognized gain on sale, unconsolidated affiliates and reversal of basis differences | $ 35,000 |  |  |  |  |  |  |

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