DEBT OBLIGATIONS - Mortgage Payable (Details) - Mortgages - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt face amount		$ 43,887,000
San Marcos, TX \| Mortgages Maturing October 2025
Debt Instrument [Line Items]
Debt face amount	$ 17,158,000
Interest rate (as a percent)	4.42%
Fredricksburg, VA \| Mortgages Maturing January 2028
Debt Instrument [Line Items]
Debt face amount		$ 26,755,000
Interest rate (as a percent)		3.68%
Fredricksburg, VA - supplemental \| Mortgages Maturing February 2027
Debt Instrument [Line Items]
Debt face amount		$ 2,208,000
Interest rate (as a percent)		4.84%
Houston, TX \| Mortgages Maturing August 2021
Debt Instrument [Line Items]
Debt face amount		$ 11,216,000
Interest rate (as a percent)		4.07%
Houston, TX - supplemental \| Mortgages Maturing August 2021
Debt Instrument [Line Items]
Debt face amount		$ 3,708,000
Interest rate (as a percent)		4.94%
Multi-family residential
Debt Instrument [Line Items]
Mortgage debt outstanding	$ 134,038,000
Debt, weighted average interest rate (as a percentage)	4.15%
Average maturity	5 years 4 months 24 days

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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