Investment in 111 West 57th Partners LLC (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended
	Feb. 28, 2015	Mar. 31, 2014	Dec. 31, 2014 sqft Agreement	Dec. 31, 2013
Investment in 111 West 57th Partners LLC [Abstract]
Amount of the investment			$ 56,000,000
Percentage ownership (in hundredths)			59.00%
Additional indirect contribution			1,250,000
Additional ownership acquired through indirect contribution (in hundredths)			1.30%
Additional contributions made by other partners in the agreement			37,750,000
Description of partnership agreement distribution			The JV Agreement and related operating agreements generally provide that all distributable cash shall be distributed as follows: (i) first, 100% to the members in proportion to their percentage interests until Investment LLC has received distributions yielding a 20% internal rate of return as calculated; (ii) second, 100% to the Sponsor as a return of (but not a return on) any additional capital contributions made by the Sponsor on account of manager overruns; and (iii) thereafter, (a) 50% to the members in proportion to their respective percentage interests at the time of such distribution, and (b) 50% to the Sponsor.
Subordinated participation interest to CEO (in hundredths)		10.00%
Percentage of distribution on company's initial investment expected to be received (in hundredths)		150.00%
Initial aggregate investment in Investment LLC		57,250,000
Number of purchase agreements			3
Noncontrolling Interest [Line Items]
Additional capital contributions			17,010,000
Amount Company was to contribute to Joint Venture pursuant to capital call	7,300,000		10,300,000
Amount of contribution to Joint Venture pursuant to capital call	700,000		1,500,000
Sponsor calculation of Investment LLC aggregate investment % after dilution (in hundredths)	45.00%		50.00%
Area of Real Estate Property			346,000
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			867,000
Equity Method Investment, Summarized Financial Information, Assets [Abstract]
Real estate held for development, net			326,387,000	263,312,000
Escrow deposits			26,011,000	43,100,000
Other assets			16,370,000	18,062,000
Total assets			368,768,000	324,474,000
Equity Method Investment, Summarized Financial Information, Liabilities [Abstract]
Mortgage payable			230,000,000	230,000,000
Other liabilities			8,319,000	2,767,000
Total liabilities			238,319,000	232,767,000
Equity:
Total equity			130,449,000	91,707,000
Total liabilities and equity			368,768,000	324,474,000
Income (Loss) [Abstract]
Rental income			1,039,000	1,106,000
Expenses			4,526,000	2,962,000
Net income (loss)			(3,487,000)	(1,856,000)
Investment LLC [Member] | Capital LLC [Member]
Noncontrolling Interest [Line Items]
Contribution to Investment LLC by non-controlling interest			$ 4,100,000
Percentage of non-controlling interest in Investment LLC			5.80%
Percentage of outstanding shares to be owned by CEO, minimum (in hundredths)			20.00%
Terms of distributions to Capital LLC			available cash of Investment LLC will be distributed first to Capital LLC until it has received a 20% internal rate of return (calculated as provided for in the JV Agreement), second to the Company until it has received 150% of its capital, and; thereafter, available cash is split 10/90 with 10% going to Mr. R.A. Bianco as the subordinated participation interest noted and 90% going to Capital LLC and the Company pari-passu, with Capital LLC receiving one-half of its pro-rata share based on capital contributed and the Company receiving the balance.