INCOME TAXES: (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits
Balance at January 1	$ 825	$ 922	$ 825
Additions based on tax positions related to the current year	114	298	174
Additions based on tax positions related to prior years	0	0	0
Reductions due to the statute of limitations	(72)	(395)	(77)
Balance at December 31	$ 867	$ 825	$ 922