ACCOUNTS RECEIVABLE (SCHEDULE OF CHANGE IN ALLOWANCE) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
ACCOUNTS RECEIVABLE AND SIGNIFICANT CLIENTS [Abstract]
Balance, beginning of year	$ 5,452	$ 5,592
Provision for credit losses	162
Uncollectible receivables written-off	(208)	(15)
Effect of foreign currency	(4)	2
Balance, end of year	$ 5,402	$ 5,579