COMMITMENTS AND CONTINGENCIES (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) lawsuit	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Malpractice Insurance [Line Items]
Number of professional liability lawsuits | lawsuit	79
Cash expenditures for self-insured professional liability costs	$ 1,549,000	$ 1,840,000
Other Insurance
Liability for workers compensation claims	1,115,000		$ 1,039,000
Workers compensation insurance, non current receivable for excess premiums paid	$ 2,123,000		2,050,000
CID
Malpractice Insurance [Line Items]
Settlement payment period	5 years
Payments made during period	$ 1,000,000	$ 500,000
Outstanding related to settlement agreement	8,000,000		9,000,000
Current loss accrual	1,000,000
Noncurrent loss accrual	$ 7,000,000		8,000,000
CIA term	5 years
Self-insurance receivables, current portion
Malpractice Insurance [Line Items]
Estimated insurance recovery receivables	$ 1,159,000		1,025,000
Scheduled for trial or arbitration over next 12 months
Malpractice Insurance [Line Items]
Number of professional liability lawsuits | lawsuit	21
Professional malpractice liability insurance
Malpractice Insurance [Line Items]
Liability for reported and estimated future claims	$ 24,824,000		24,744,000
Professional malpractice liability insurance | SHC Risk Carriers, Inc
Malpractice Insurance [Line Items]
Insurance policy coverage limits per claim	1,000,000
Malpractice insurance annual sublimit per center	3,000,000
Aggregate policy limit	5,000,000
Other Insurance
Insurance policy coverage limits per claim	1,000,000
Prefunded deductible policy
Malpractice Insurance [Line Items]
Insurance policy coverage limits per claim	500,000
Other Insurance
Insurance policy coverage limits per claim	500,000
Professional liability insurance, annual coverage limit per facility	3,000,000
Health insurance, maximum self-insured annual amount per individual	200,000
Liability for reported claims and estimates for incurred but unreported claims	$ 2,268,000		$ 2,358,000