OTHER LONG TERM LIABILITIES (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Liabilities, Noncurrent [Abstract]
Deferred revenue - long-term	$ 26,193	$ 33,247
Deferred Compensation Liability, Classified, Noncurrent	18,598	14,836
Payable for remaining portion of acquisition		37,756
Other Accrued Liabilities, Noncurrent	29,435	40,693
Other Liabilities, Noncurrent, Total	$ 74,226	$ 126,532