Subsequent Event (Details) (Subsequent event [Member], Jowein building in Brooklyn, New York [Member], USD $)	1 Months Ended
	May 31, 2015 sqft
Subsequent event [Member] | Jowein building in Brooklyn, New York [Member]
Subsequent Event [Line Items]
Term of lease	20 years
Office space (in square feet)	17,425
Rent	$ 550,000
Brokerage commissions	500,000
Construction costs	$ 2,000,000