Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Real Estate - Schedule of Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Real Estate [Line Items]
Total Purchase Price	$ 2,019,058	$ 1,948,165
Ashbrook Marketplace
Real Estate [Line Items]
Land		8,776
Buildings		0
Total Purchase Price		8,776
7316 Wisconsin Avenue
Real Estate [Line Items]
Land		38,686
Buildings		979
Total Purchase Price		40,698
2018 Acquisitions
Real Estate [Line Items]
Land		47,462
Buildings		979
Total Purchase Price		49,474
In-place Leases \| Ashbrook Marketplace
Real Estate [Line Items]
Intangible assets		0
In-place Leases \| 7316 Wisconsin Avenue
Real Estate [Line Items]
Intangible assets		(886)
In-place Leases \| 2018 Acquisitions
Real Estate [Line Items]
Intangible assets		(886)
Above Market Rent \| Ashbrook Marketplace
Real Estate [Line Items]
Intangible assets		0
Above Market Rent \| 7316 Wisconsin Avenue
Real Estate [Line Items]
Intangible assets		(168)
Above Market Rent \| 2018 Acquisitions
Real Estate [Line Items]
Intangible assets		(168)
Below Market Rent \| Ashbrook Marketplace
Real Estate [Line Items]
Intangible assets		0
Below Market Rent \| 7316 Wisconsin Avenue
Real Estate [Line Items]
Intangible assets		(21)
Below Market Rent \| 2018 Acquisitions
Real Estate [Line Items]
Intangible assets		$ (21)