Investments in Unconsolidated Real Estate Ventures - Summary of Unaudited Information Related to Real Estate Ventures' Debt (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
VRS [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 52,100
Current Interest Rate	3.19%
Debt Maturity	June 2020
PREXR {Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 0
Current Interest Rate	0.00%
Debt Maturity	Unleveraged
SPI [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 86,285
Current Interest Rate	4.66%
Debt Maturity	April 2018
PRISA [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 0
Current Interest Rate	0.00%
Debt Maturity	Unleveraged
ESW II [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 18,072
Current Interest Rate	3.57%
Debt Maturity	February 2019
Clarendon [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 7,596
Current Interest Rate	5.93%
Debt Maturity	September 2018
ESSM [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 13,374
Current Interest Rate	2.52%
Debt Maturity	May 2021
WCOT [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 87,500
Current Interest Rate	3.34%
Debt Maturity	August 2019
ESW [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 17,150
Current Interest Rate	2.02%
Debt Maturity	August 2020
ESNPS [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 35,500
Current Interest Rate	2.12%
Debt Maturity	July 2025
Other Minority Owned Properties [Member]
Schedule of Equity Method Investments [Line Items]
Loan Amount	$ 67,087
Debt Maturity	Various

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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