DISPOSITIONS AND IMPAIRMENTS - 2023 Disposition Activity (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) property	Dec. 31, 2022 USD ($) property	Dec. 31, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	1,355
Proceeds from real estate disposals | $	$ 399,534	$ 112,926	$ 840,438
Gain on real estate dispositions | $	62,119	7,780	218,788
Dispositions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from real estate disposals | $	399,500	$ 115,100	$ 859,700
Gain on real estate dispositions | $	$ 62,100
Dispositions | Land
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	2	1
Dispositions | SHOP
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	7
Dispositions | Vacant Senior Living Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	4
Dispositions | Outpatient Medical Buildings And Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	7
Dispositions | Research Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	3
Dispositions | Triple-net leased properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	9
Dispositions | Vacant Triple Net Leased Properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Properties	2