GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS--Schedule of Goodwill (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Goodwill [Roll Forward]
Balance at beginning of period	$ 204,084	$ 204,084	$ 204,084
Goodwill	678,941	$ 0	0
Balance at end of period	$ 883,025		$ 204,084