NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Supplemental Information - Statement of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income taxes paid	$ 16,928	$ 128,168	$ 108,347
Income tax refunds	413	1,508	12,193
Interest paid	284,691	203,800	191,117
Non- cash transactions
Non-cash transaction property and equipment	$ 10,600	$ 9,500	$ 5,900