Schedule III - Real Estate and Accumulated Depreciation (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Real Estate Properties [Line Items]
Description	Office building and land located at 250-264 West 57th Street, New York, New York, known as the “Fisk Building”.	Office building and land located at 250-264 West 57th Street, New York, New York, known as the “Fisk Building”.
Encumbrances
Prudential Insurance Company of America and Signature Bank at December 31	$ 52,900,635	$ 44,935,520
Initial cost to company
Land	2,117,435	2,117,435
Building	4,940,682	4,940,682
Cost capitalized subsequent to acquisition
Building improvements (net of $249,791 written off in 2003)	50,989,946	44,605,623
Carrying costs
Gross amount at which carried at close of period
Land	2,117,435	2,117,435
Building, building and tenant improvements	55,930,628	49,546,305
Total	58,048,063	51,663,740
Accumulated depreciation (net of $249,791 written off in 2003)	13,651,197	12,512,188
Date of construction	1921	1921
Date acquired	Sep. 30, 1953	Sep. 30, 1953
Life on which depreciation in latest income statements is computed Gross amount of real estate	39 years	39 years
Gross amount of real estate, Beginning Balance	51,663,740	46,904,759
Purchase of building improvements and building improvements in progress (expenditures advanced by Lessee, a related party, and recorded by the Company):	7,072,323	4,758,981
Gross amount of real estate, Assets sold / written off		(2,805,435)
Gross amount of real estate, Ending Balance	58,048,063	51,663,740
Accumulated depreciation, beginning Balance	12,512,188	11,009,975
Depreciation	1,827,010	1,502,213
Accumulated depreciation, Assets sold / written off		(688,001)
Accumulated depreciation, Ending Balance	$ 13,651,197	$ 12,512,188