Schedule III Real Estate and Accumulated Depreciation (Parenthetical) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Real Estate And Accumulated Depreciation [Line Items]
Aggregate net tax value of real estate assets for federal income tax purposes	$ 550
Minimum | Lease Intangibles
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	12 years
Maximum | Lease Intangibles
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	15 years
Building and Improvements | Minimum
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	2 years
Building and Improvements | Maximum
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	50 years
Furniture, Fixtures, and Equipment | Minimum
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	5 years
Furniture, Fixtures, and Equipment | Maximum
Real Estate And Accumulated Depreciation [Line Items]
Estimated useful lives of assets	14 years