SEGMENT REPORTING (Total Assets by Geographical Area) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 3,774,329	$ 3,706,570
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	3,090,011	2,985,394
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	684,144	721,176
Other foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 174	$ 0