Real Estate Properties - Summary of Balance Sheet Information for all Properties Classified as Held for sale (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Liabilities related to properties held for sale	$ 667	$ 0
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate properties	12,952
Other assets, net	511
Properties held for sale	13,463
Accounts payable and accrued expenses	337
Rent collected in advance	19
Security deposits	311
Liabilities related to properties held for sale	$ 667

Disposal Group, Including Discontinued Operation, Real Estate Properties

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount classified as deferred revenue attributable to disposal group held for sale or disposed of.

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