INCOME TAXES - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current [Abstract]
Federal		$ 18,296	$ 20,102	$ 28,765
Foreign		4,060	3,015	2,670
State		3,880	2,790	2,483
Deemed repatriation	$ 1,389	(970)	1,389	0
Deferred [Abstract]
Federal		(3,788)	(1,302)	(7,114)
Foreign		(69)	62	52
State		(952)	(384)	106
Federal rate change		0	(27,255)	0
Total income tax provision		$ 20,457	$ (1,583)	$ 26,962