MORTGAGE DEBT - Mortgage Debt, Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) acquisition property loan	Dec. 31, 2020
Debt Instrument [Line Items]
Number of acquisitions partially financed with mortgages | acquisition	8
Number of existing mortgages refinanced | loan	6
Number of properties that acquired supplemental financing | property	2
Mortgage debt
Debt Instrument [Line Items]
Weighted-average interest rate of investment debt (as a percent)	3.11%	3.31%
Percent of property level debt with fixed rate (as a percent)	78.00%	73.00%
Percent of property level debt with floating rate and interest caps (as a percent)	13.00%	13.00%
Percent of property level debt with floating rate, without interest caps (as a percent)	9.00%	14.00%
Total waivers on debt covenants in loan agreements | $	$ 71.9
Percent of consolidated mortgage balance	200.00%