SEGMENT REPORTING (Total Assets by Geographical Area) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 3,748,353	$ 3,681,920
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	3,005,644	2,960,337
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 742,709	$ 721,583