INVESTMENT IN REAL ESTATE PROPERTIES - Senior Housing - Managed Communities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Real Estate [Line Items]
Resident fees and services	$ 39,341	$ 36,405	$ 117,908	$ 89,537
Ancillary Services
Real Estate [Line Items]
Resident fees and services	$ 300	$ 200	$ 700	$ 500

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details