Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jul. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Significant Of Accounting Policies [Line Items]
Assets excluding BREIT OP	$ 36,628,499	$ 36,628,499			$ 33,039,823
Liabilities excluding BREIT OP	22,037,333	22,037,333			22,404,026
Investments in equity securities	348,261	348,261
Impairment of investments in real estate	6,126	6,126	$ 0
Granted deferred rent	$ 99,963	$ 99,963			38,287
Subsequent Event [Member]
Significant Of Accounting Policies [Line Items]
Granted deferred rent				$ 6,100
Discount Rate [Member]
Significant Of Accounting Policies [Line Items]
Estimated fair value of impaired property, assumptions	0.087	0.087
Exit Capitalization Rate [Member]
Significant Of Accounting Policies [Line Items]
Estimated fair value of impaired property, assumptions	0.057	0.057
One Hotel Properties [Member]
Significant Of Accounting Policies [Line Items]
Impairment of investments in real estate	$ 6,100	$ 6,100
Level 2 [Member]
Significant Of Accounting Policies [Line Items]
Investments in real estate-related securities	4,600,000	4,600,000			4,500,000
Level 1 [Member]
Significant Of Accounting Policies [Line Items]
Investments in equity securities	348,300	348,300
Level 3 [Member]
Significant Of Accounting Policies [Line Items]
Mortgage notes, term loans, secured and unsecured revolving credit facilities, repurchase agreements, and affiliate line of credit	89,600	89,600			54,900
VIEs [Member]
Significant Of Accounting Policies [Line Items]
Assets excluding BREIT OP	11,300,000	11,300,000			9,500,000
Liabilities excluding BREIT OP	$ 8,000,000	$ 8,000,000			$ 6,600,000