Property Dispositions and Real Estate Impairment - Schedule of Properties Held for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Real estate, at cost	$ 2,827	$ 25,957
Real estate, intangible assets	0	7,789
Accumulated depreciation and amortization	0	(13,346)
Rent receivable - deferred	0	1,715
Other	0	1,693
Assets held for sale	2,827	23,808
Other	0	191
Liabilities held for sale	$ 0	$ 191