FINANCING ARRANGEMENTS (Summary of Financing Arrangements) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 7,535	$ 7,535
Long-term obligations, at par	1,572,162	1,579,697
Unamortized debt issuance costs and premium, net	(18,046)	(14,676)
Long-term obligations, at carrying value	1,554,116	1,565,021
Secured debt \| Senior secured Term Loan Agreement
Debt Instrument [Line Items]
Current portion of long-term obligations	7,535	7,535
Long-term obligations, at par	727,162	734,697
Unsecured debt \| Unsecured senior notes, at 4.875%, due July 15, 2027 (2027 Notes)
Debt Instrument [Line Items]
Long-term obligations, at par	$ 545,000	0
Interest rate (as a percent)	4.875%
Unsecured debt \| Unsecured senior notes, at 5.125%, due July 15, 2029 (2029 Notes)
Debt Instrument [Line Items]
Long-term obligations, at par	$ 300,000	0
Interest rate (as a percent)	5.125%
Unsecured debt \| Unsecured senior notes, at 5.125%, due June 1, 2021 (2021 Notes)
Debt Instrument [Line Items]
Long-term obligations, at par	$ 0	$ 845,000
Interest rate (as a percent)	5.125%

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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