SEGMENT REPORTING (Total Assets by Geographical Area) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 3,684,816	$ 3,706,570
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	3,002,779	2,985,394
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	681,901	721,176
Other foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Total assets	$ 136	$ 0