FINANCING ARRANGEMENTS - Summary of Financing Arrangements (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 7,535	$ 7,535
Long-term obligations	1,643,394	1,572,162
Unamortized debt issuance costs and premium, net	(16,523)	(18,046)
Long-term obligations, at carrying value	1,626,871	1,554,116
Secured debt \| Term Loan Agreement
Debt Instrument [Line Items]
Current portion of long-term obligations	7,535	7,535
Long-term obligations	723,394	727,162
Unsecured debt \| Unsecured senior notes, at 4.875%, due July 15, 2027 ("2027 Notes")
Debt Instrument [Line Items]
Long-term obligations	$ 545,000	545,000
Interest rate (as a percentage)	4.875%
Unsecured debt \| Unsecured senior notes, at 5.125%, due July 15, 2029 ("2029 Notes")
Debt Instrument [Line Items]
Long-term obligations	$ 300,000	300,000
Interest rate (as a percentage)	5.125%
Line of Credit \| Revolving credit facility
Debt Instrument [Line Items]
Long-term obligations	$ 75,000	$ 0

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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