Investments in Real Estate - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed (Detail) $ in Thousands			4 Months Ended	9 Months Ended
	Jun. 19, 2020 loan	Mar. 05, 2020 loan	Jun. 19, 2020 loan	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
ASSETS
Land				$ 251,672
Buildings and improvements				100,975
Tenant improvements				2,023
Acquired lease intangible assets(1)				12,421
Other acquired assets(2)				3,082
Total assets acquired				370,173
Liabilities
Acquired lease intangible liabilities(3)				10,590
Notes payable(4)				48,759
Other assumed liabilities(2)				1,632
Total liabilities assumed				60,981
Net assets acquired				$ 309,192
Intangible Assets [Abstract]
Below-market lease intangibles, weighted average amortization period				5 years 10 months 24 days
Assumption of debt in connection with acquisition of real estate including loan premium				$ 48,759	$ 0
In-place lease intangibles
Intangible Assets [Abstract]
In-place lease intangibles				$ 12,200
Weighted average amortization period				4 years 7 months 6 days
Above-market tenant leases
Intangible Assets [Abstract]
Weighted average amortization period				7 years 10 months 24 days
Above-market lease intangibles				$ 200
Properties Acquired on March 5, 2020 and June 19, 2020
Intangible Assets [Abstract]
Number Of Mortgage Loans Assumed | loan	1	9	10