SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash paid for:
Interest	$ 44,250	$ 25,788
Income taxes	11,621	14,594
Non-cash investing activities:
Property and equipment accrued in accounts payable	$ 595	$ 40