DEBT - Schedule of long-term debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
LONG-TERM DEBT
Finance Lease Obligations	$ 7,690	$ 7,780
Long-term debt, gross	629,610	600,110
Less: discounts and fees, net of accumulated amortization	(11,717)	(12,496)
Less: current maturities	(38,011)	(38,779)
Long-term debt, less current portion	579,882	548,835
Assigned Clinic Loans due to Term Loan Holdings
LONG-TERM DEBT
Long-term debt, gross	250	866
Other Term Loans
LONG-TERM DEBT
Long-term debt, gross	90,107	92,958
Other Lines of Credit
LONG-TERM DEBT
Long-term debt, gross	4,763	5,006
2017 Credit Agreement \| 2017 Credit Agreement - Term B Loan Facility
LONG-TERM DEBT
Long-term debt, gross	426,800	429,000
Revolving Credit Facility \| 2017 Credit Agreement \| 2017 Credit Agreement - Revolving Credit Facility
LONG-TERM DEBT
Long-term debt, gross	$ 100,000	$ 64,500

Long-term Debt, Gross And Lease Obligation, Gross

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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