Real Estate Investments (Textual) (Details) $ in Thousands		3 Months Ended		9 Months Ended
	Sep. 11, 2019 USD ($) ft²	Sep. 30, 2019 USD ($) a	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) a parcel	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sale		$ 250	$ 0	$ 1,501	$ 2,859
Additional gain on prior disposal		700
Assets held for sale, net		7,349		7,349		$ 11,599
Assets Held-for-sale | Land Held For Development
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale, net		$ 7,300		$ 7,300
Assets Held-for-sale | Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of parcels of land | parcel				2
Area of land (in acres) | a		35.2		35.2
Land
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales price		$ 5,325		$ 5,325
Gain (loss) on sale				$ 1,501
Number of parcels of land | parcel				1
Area of land (in acres) | a		2.7		2.7
Land | 1900 Gallows Rd.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable area (in square feet) | ft²	210,632
Sales price	$ 36,400
Gain (loss) on sale	$ (400)