Real Estate Properties - Summary of Balance Sheet Information for all Properties Classified as Held for sale (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Liabilities related to properties held for sale	$ 1,013	$ 0
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate properties	61,829
Other assets, net	2,567
Properties held for sale	64,396
Accounts payable and accrued expenses	150
Security deposits	863
Liabilities related to properties held for sale	$ 1,013

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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