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Leases - Schedule of Supplemental Balance Sheet Information Related to Leases (Parenthetical) (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Leases [Line Items] |  |
Operating lease right-of-use assets, net | $ 8,286,694 | $ 4,392,481
Operating lease liabilities - long-term | 8,390,117 | 4,277,970
Bellagio BREIT Venture [Member] |  |
Leases [Line Items] |  |
Operating lease right-of-use assets, net | 3,700,000 | 3,700,000
Operating lease liabilities - long-term | 3,800,000 | 3,700,000
Mandalay Bay and MGM Grand Las Vegas [Member] |  |
Leases [Line Items] |  |
Operating lease right-of-use assets, net | 4,000,000 | 0
Operating lease liabilities - long-term | $ 4,100,000 | $ 0

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- Definition Leases. + References No definition available. + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977 + Details
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