ASSETS HELD FOR SALE - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current liabilities held for sale	$ 4,210	$ 4,210	$ 5,767
Certain Clinics In Pennsylvania, Ohio, and New Jersey and Other Property and Equipment \| Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Increase (decrease) in valuation allowance	7	(498)
Current assets held for sale	49,197	49,197	50,099
Current liabilities held for sale	4,210	4,210	$ 5,767
Revenue	$ 6,846	$ 13,619

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