CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED [Abstract]
Net income	$ 11,290	$ 24,017	$ 22,535	$ 43,909
Other comprehensive income / (loss):
Foreign currency translation loss	(4)	(23)	(65)	(3)
Total comprehensive income	$ 11,286	$ 23,994	$ 22,470	$ 43,906