LOANS PAYABLE AND SECURED LINE OF CREDIT - Additional Information (Details)				1 Months Ended			12 Months Ended
	Feb. 28, 2020	Dec. 19, 2019 USD ($) item $ / shares	May 11, 2016 USD ($)	May 25, 2018	Dec. 22, 2017 USD ($) ft²	Feb. 22, 2017	Dec. 31, 2019 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($) $ / shares	May 24, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Aug. 04, 2017 USD ($)	Dec. 31, 2016 USD ($)
Interest Costs Capitalized							$ 497,000
Common Stock, Par Value Per Share | $ / shares							$ 0.01		$ 0.01
Line of Credit Facility, Maximum Borrowing Capacity							$ 70,000,000
Long-term Line of Credit							5,236,000		$ 0
Line of Credit Facility, Expiration Date						Feb. 22, 2019
Loans Payable							169,735,000		123,333,000
Debt Instrument, Interest Rate Terms				bearing interest at a blended average rate of 3.72% over the 30-day LIBOR, each with a one year extension option upon satisfaction of certain conditions
Debt Instrument, Payment Terms				a guaranty of 25% of the principal amount, decreasing to 10% of the principal balance upon the debt yield ratio becoming equal to or greater than 7.0%
Cash and cash equivalents							$ 9,196,000		$ 11,496,000		$ 15,273,000			$ 4,678,000
Maximum [Member]
Debt Instrument, Interest Rate, Stated Percentage					2.50%
Loans Payable [Member]
Debt Instrument, Interest Rate, Effective Percentage							5.48%		6.22%
Debt Instrument, Face Amount										$ 67,800,000
Letter of Credit [Member]
Debt Instrument, Interest Rate, Effective Percentage							3.76%
Loans Payable							$ 5,300,000
Subsequent Event [Member]
Term of the debt	5 years
Landmarked Robert And Anne Dickey House [Member]
Area of Real Estate Property | ft²					7,500
Sterling National Bank [Member]
Debt Instrument, Description of Variable Rate Basis						100	200
Line of Credit Facility, Maximum Borrowing Capacity							$ 12,750,000					$ 11,000,000
Secured Debt													$ 9,100,000
Interest Rate Cap [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivative Asset, Fair Value, Gross Asset							$ 0		$ 497,000
West Palm Beach Florida Loan [Member]
Debt Instrument, Interest Rate, Basis for Effective Rate			interest at 30-day LIBOR plus 230 basis points
Line of Credit Facility, Maximum Borrowing Capacity			$ 12,600,000
Derivative, Notional Amount			$ 10,600,000
Greenwich Construction Loan [Member]
Debt Instrument, Interest Rate, Effective Percentage							10.01%		10.60%
Debt Instrument, Unamortized Premium					$ 393,000
Derivative, Notional Amount					189,500,000
Debt Instrument, Face Amount					$ 189,500,000
Number of Real Estate Properties					90
Debt Instrument, Description					LIBOR plus 8.25% and (ii) 9.25%.
Loans Payable							$ 104,900,000		$ 51,500,000
Cash and cash equivalents					$ 15,000,000			$ 10,000,000
Greenwich Construction Loan [Member] | Letter of Credit [Member]
Loans Payable							$ 7,000,000
Corporate Loan [Member]
Term of the debt		32 months
Increase in maximum borrowing capacity		$ 25,000,000
Commitment fee		$ 2,450,000
Commitment fee, payable on the initial draw (as a percent)		50.00%
Commitment fee, payable on subsequent draws (as a percent)		50.00%
Exit fee (as a percent)		1.00%
Multiple On Invested Capital (as a percent)		130.00%
Collateral for loan, equity interests in subsidiaries (as a percent)		100.00%
Common stock repurchase through proceeds from debt, amount authorized		$ 2,000,000
Common Stock, Par Value Per Share | $ / shares		$ 0.01
Common stock repurchase through other sources of cash, amount authorized		$ 1,500,000
Threshold minimum loan outstanding (as a percent)		50.00%
Number of board members who can be appointed by the lender | item		1
Maximum number of committees of the board, that the Designee can sit | item		3
Line of Credit Facility, Maximum Borrowing Capacity		$ 70,000,000
Debt Instrument, Interest Rate Terms		a rate per annum equal to the sum of (i) 5.25% (the "PIK Interest Rate") and (ii) a scheduled interest rate (the "Cash Pay Interest Rate") based on six-month periods from the Closing Date, which Cash Pay Interest Rate, from the Closing Date until the six-month anniversary of the Closing Date, equals 4.0%, subject to increase during the extension periods.
Corporate Loan [Member] | Greenwich Ny 77 [Member]
Net cash proceeds of residential condominium sales (as a percent)		70.00%
Corporate Loan [Member] | PIK Interest Rate
Interest rate basis (as a percent)		5.25%
Corporate Loan [Member] | Cash Pay Interest Rate
Interest rate basis (as a percent)		4.00%
Corporate Loan [Member] | Minimum [Member]
Net cash proceeds of residential condominium sales (as a percent)		90.00%
Corporate Loan [Member] | Maximum [Member]
Net cash proceeds of residential condominium sales (as a percent)		100.00%
Canadian Imperial Bank of Commerce [Member] | Loans Payable [Member]
Debt Instrument, Face Amount										52,400,000
Debt, Weighted Average Interest Rate							0.50%
RCG LV Debt VI REIT LLC [Member] | Mezzanine Loan [Member]
Debt Instrument, Face Amount										$ 15,400,000