ACCOUNTS RECEIVABLE (SCHEDULE OF CHANGE IN ALLOWANCE) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
ACCOUNTS RECEIVABLE AND SIGNIFICANT CLIENTS [Abstract]
Balance, beginning of year	$ 4,997	$ 5,402	$ 5,067	$ 5,452
Provision for credit losses	135	445	155	607
Uncollectible receivables written-off	(178)	(107)	(261)	(285)
Effect of foreign currency	(2)	55	(9)	21
Acquisition credit losses	988		988
Balance, end of year	$ 5,940	$ 5,795	$ 5,940	$ 5,795