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Investments in and Advances to Unconsolidated Affiliates - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Apr. 30, 2020 | Apr. 30, 2019 | Mar. 31, 2019 | Sep. 30, 2020 | Sep. 30, 2020 | Sep. 30, 2019
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |
Distributions from unconsolidated affiliates |  |  |  |  | $ 63,578 | $ 99,661
Other-than-temporary impairment charges |  |  |  |  | 64,000 |
City Center Holdings L L C [Member] |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |
Distribution paid/declared | $ 101,000 | $ 116,000 | $ 64,000 |  |  |
MGP BREIT Venture [Member] |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |
Distributions from unconsolidated affiliates |  |  |  | $ 23,000 | $ 58,000 |
CityCenter Holdings LLC As Investee [Member] |  |  |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |  |  |
Distributions from unconsolidated affiliates | $ 51,000 | $ 58,000 | $ 32,000 |  |  |
Distributions from unconsolidated affiliates, percentage | 50.00% | 50.00% | 50.00% |  |  |

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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562 + Details
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