IMPAIRMENT OF REAL ESTATE AND DISPOSITIONS - Dispositions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) facility	Dec. 31, 2022 USD ($) facility	Dec. 31, 2021 USD ($) facility
Dispositions:
Number of facilities | facility	28	18	16
Consideration, net of closing costs	$ 255.6	$ 87.3	$ 103.4
Net carrying value	332.2	99.3	92.1
Net (loss) gain on sale	(76.6)	(12.0)	11.3
Net income (loss)	(80.9)	(94.8)	21.5
Impairment upon disposal	$ 7.1	$ 94.0	$ 9.5
Disposal group, not discontinued operations, gain (loss) on disposal, statement of income	Net (loss) gain on sale