Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Mortgage Loans Receivable and Notes Receivable (Details) - USD ($)	1 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2019
Real Estate Properties [Line Items]
Mortgage loans receivable		$ 0	$ 43,276,000
Multi Family Same-Store \| Ironwood \| Tax Increment Financing
Real Estate Properties [Line Items]
Loan commitment	$ 6,600,000	6,100,000	6,400,000
Interest rate on mortgages payable	4.50%
Multi Family Residential \| Minneapolis, Minnesota \| Construction Loans
Real Estate Properties [Line Items]
Mortgage loans receivable		$ 0	29,900,000	$ 29,900,000
Interest rate on mortgages payable		4.50%
Multi Family Residential \| Minneapolis, Minnesota \| Mezzanine Loan
Real Estate Properties [Line Items]
Mortgage loans receivable		$ 0	$ 13,400,000	$ 15,300,000
Interest rate on mortgages payable		11.50%