Summary of Significant Accounting Policies - Estimated Useful Lives of Related Real Estate and Other Assets (Detail)	12 Months Ended
	Dec. 31, 2019
Buildings and improvements [Member]
Property, Plant and Equipment [Line Items]
Weighted average useful lives of related real estate and other assets	39 years
Tenant lease intangibles [Member]
Property, Plant and Equipment [Line Items]
Weighted average useful lives of related real estate and other assets	23 years 8 months 12 days
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Weighted average useful lives of related real estate and other assets	17 years
Furniture, equipment and other [Member]
Property, Plant and Equipment [Line Items]
Weighted average useful lives of related real estate and other assets	7 years 8 months 12 days