Investment in Unconsolidated Joint Venture - Condensed Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Oct. 30, 2013
Schedule of Equity Method Investments [Line Items]
Real estate assets, at cost	$ 1,895,860	$ 1,888,366
Less accumulated depreciation and amortization	(146,445)	(124,178)
Total real estate investments, net	1,749,415us-gaap_RealEstateInvestmentPropertyNet	1,764,188us-gaap_RealEstateInvestmentPropertyNet
Total assets	2,092,823us-gaap_Assets	2,120,835us-gaap_Assets
Debt	427,900us-gaap_NotesPayable
Total liabilities	925,586us-gaap_Liabilities	925,158us-gaap_Liabilities
Deficit	(282,323)	(255,478)
Total liabilities and equity	2,092,823	2,120,835
Worldwide Plaza
Schedule of Equity Method Investments [Line Items]
Real estate assets, at cost	704,257	704,143
Less accumulated depreciation and amortization	(102,127)	(97,181)
Total real estate investments, net	602,130	606,962
Other assets	261,698	255,784
Total assets	863,828	862,746
Debt	875,000	875,000	875,000
Other liabilities	10,765	12,442
Total liabilities	885,765	887,442
Deficit	(21,937)	(24,696)
Total liabilities and equity	863,828	862,746
Company's basis	$ 225,736	$ 225,501

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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