Dispositions and Impairment - Schedule of Properties Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Liabilities:
Liabilities held for sale	$ 1,446	$ 0
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Assets:
Real estate, at cost	125,878	2,827
Real estate, intangible assets	15,352	0
Accumulated depreciation and amortization	(13,881)	0
Rent receivable - deferred	4,897	0
Other	2,498	0
Assets held for sale	134,744	2,827
Liabilities:
Accounts payable and other liabilities	162	0
Prepaid rent	546	0
Deferred rent - below market lease, net	738	0
Liabilities held for sale	$ 1,446	$ 0

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