STOCK REPURCHASE PROGRAM (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Oct. 20, 2016
STOCK REPURCHASE PROGRAM
Share repurchases authorized amount					$ 350,000
Aggregate amount of share repurchases (in dollars)			$ 3,905	$ 26,728
Common stock repurchased (retired and held in treasury) (in shares)	480	613	668	822
Common stock repurchased (retired and held in treasury)	$ 45,000	$ 51,700	$ 61,700	$ 67,700
Common stock repurchased and retired (in shares)			623	512
Common stock repurchased and retired			$ 57,787	$ 40,994
Remaining authorized repurchase amount	$ 80,200		$ 80,200