Debt - Schedule of long term-term debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
LONG-TERM DEBT
Present value of lease liabilities	$ 7,780
Finance Lease Obligations		$ 6,706
Long-term debt, gross and lease obligation, gross	600,110	568,439
Less: discounts and fees, net of accumulated amortization	(12,496)	(8,073)
Less: current maturities	(38,779)	(42,855)
Long-term debt excluding current maturities	548,835	517,511
Loans Payable
LONG-TERM DEBT
Carrying amount of debt	866	5,078
Other Term Loans
LONG-TERM DEBT
Carrying amount of debt	92,958	113,866
Other Line Of Credit
LONG-TERM DEBT
Carrying amount of debt	5,006	1,849
Other
LONG-TERM DEBT
Carrying amount of debt	$ 0	2,040
Minimum
LONG-TERM DEBT
Interest rate	4.33%
Minimum \| Term Loans
LONG-TERM DEBT
Interest rate	3.65%
Minimum \| Lines of Credit
LONG-TERM DEBT
Interest rate	4.13%
Maximum
LONG-TERM DEBT
Interest rate	8.08%
Maximum \| Term Loans
LONG-TERM DEBT
Interest rate	6.55%
Maximum \| Lines of Credit
LONG-TERM DEBT
Interest rate	7.68%
2017 Credit Agreement \| Term Loans
LONG-TERM DEBT
Carrying amount of debt	$ 429,000	433,400
Revolving Credit Facility \| 2017 Credit Agreement \| Lines of Credit
LONG-TERM DEBT
Carrying amount of debt	$ 64,500	$ 5,500

Long-term Debt, Gross And Lease Obligation, Gross

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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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.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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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.

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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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