Investments in Unconsolidated Entities - Summary of Income From Unconsolidated Entities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule Of Equity Method Investments [Line Items]
Income from unconsolidated entities	$ 34,682	$ 13,269
BREIT Income from Unconsolidated Entities	28,472	$ (1,200,087)
Unconsolidated Joint Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
BREIT Income from Unconsolidated Entities	$ 34,682
Unconsolidated Joint Ventures [Member] | MGM Grand and Mandalay Bay [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Interest	49.90%	49.90%
Income from unconsolidated entities	$ 50,869	$ 26,632
BREIT Income from Unconsolidated Entities	25,346	13,269
Unconsolidated Joint Ventures [Member] | MGM Grand and Mandalay Bay [Member] | BREIT's Share [Member]
Schedule Of Equity Method Investments [Line Items]
Income from unconsolidated entities	25,384	13,289
Unconsolidated Joint Ventures [Member] | MGM Grand and Mandalay Bay [Member] | BREIT Outside Basis [Member]
Schedule Of Equity Method Investments [Line Items]
Income from unconsolidated entities	(38)	(20)
Unconsolidated Joint Ventures [Member] | MGM Grand and Mandalay Bay [Member] | Rental [Member]
Schedule Of Equity Method Investments [Line Items]
Total Revenue of Unconsolidated Joint Ventures	$ 98,681	$ 50,437
Unconsolidated Joint Ventures [Member] | WC Infill Industrial Portfolio [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Interest	85.00%
BREIT Income from Unconsolidated Entities	$ 5,359
Unconsolidated Joint Ventures [Member] | Vault Industrial Portfolio [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Interest	41.00%
BREIT Income from Unconsolidated Entities	$ 3,977