Preferred Equity Investments (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Investment Holdings [Line Items]
Preferred equity investments	$ 53,941
Four Seven Zero Vanderbilt Avenue
Investment Holdings [Line Items]
Preferred equity ownership percentage	25.40%
Preferred Equity Investments, Dividend Rate	10.30%
Preferred Equity Investments, Initial Maturity	2019-02
Preferred equity investments	$ 35,305
2 Herald Square [Member]
Investment Holdings [Line Items]
Preferred equity ownership percentage	25.40%
Preferred Equity Investments, Dividend Rate	10.30%
Preferred Equity Investments, Initial Maturity	2017-04
Preferred equity investments	$ 18,636