Real Estate Properties - Summary of Balance Sheet Information for all Properties Classified as Held for sale (Details) - USD ($) $ in Thousands	Jun. 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	$ 1,687	$ 0
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate properties	136,299
Acquired real estate leases	1,751
Other assets, net	12,716
Properties held for sale	150,766
Accounts payable and accrued expenses	674
Assumed real estate lease obligations	403
Rent collected in advance	266
Security deposits	344
Liabilities related to properties held for sale	$ 1,687

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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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Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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