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Investments in and Advances to Unconsolidated Affiliates - Schedule of Investments in and Advances to Unconsolidated Affiliates (Detail) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
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Schedule Of Equity Method Investments [Line Items] |  |
Investments in and advances to unconsolidated affiliates | $ 1,484,717 | $ 1,447,043
CityCenter Holdings LLC As Investee [Member] |  |
Schedule Of Equity Method Investments [Line Items] |  |
Investments in and advances to unconsolidated affiliates | 515,472 | 441,893
MGP BREIT Venture [Member] |  |
Schedule Of Equity Method Investments [Line Items] |  |
Investments in and advances to unconsolidated affiliates | 813,850 | 810,066
BetMGM [Member] |  |
Schedule Of Equity Method Investments [Line Items] |  |
Investments in and advances to unconsolidated affiliates | 22,057 | 27,310
Other [Member] |  |
Schedule Of Equity Method Investments [Line Items] |  |
Investments in and advances to unconsolidated affiliates | $ 133,338 | $ 167,774

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- Definition Amount of investment in equity method investee and investment in and advance to affiliate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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