Investments in Real Estate - Schedule of Purchase Price Allocation of Properties (Detail) $ in Thousands	Sep. 30, 2019 USD ($)
Real Estate Properties [Line Items]
Building and building improvements	$ 8,621,620
Land and land improvements	1,830,512
Furniture, fixtures and equipment	86,000
In-place lease intangibles	558,986
Above-market lease intangibles	19,965
Below-market ground lease	15,985
Below-market lease intangibles	(90,593)
Other	20,986
Total purchase price	11,063,461
Assumed mortgage notes	1,146,823
Net purchase price	9,916,638
Jupiter 12 Industrial Portfolio [Member]
Real Estate Properties [Line Items]
Building and building improvements	4,380,115
Land and land improvements	781,578
In-place lease intangibles	346,492
Above-market lease intangibles	14,105
Below-market ground lease	15,985
Below-market lease intangibles	(71,578)
Total purchase price	5,466,697
Assumed mortgage notes	703,853
Net purchase price	4,762,844
Roman Multifamily Portfolio [Member]
Real Estate Properties [Line Items]
Building and building improvements	714,941
Land and land improvements	110,206
Furniture, fixtures and equipment	8,538
In-place lease intangibles	23,855
Total purchase price	857,540
Assumed mortgage notes	237,981
Net purchase price	619,559
All Other [Member]
Real Estate Properties [Line Items]
Building and building improvements	3,526,564
Land and land improvements	938,728
Furniture, fixtures and equipment	77,462
In-place lease intangibles	188,639
Above-market lease intangibles	5,860
Below-market lease intangibles	(19,015)
Other	20,986
Total purchase price	4,739,224
Assumed mortgage notes	204,989
Net purchase price	$ 4,534,235