RECENT ACCOUNTING PRONOUNCEMENTS RECENT ACCOUNTING PRONONCEMENTS - ASU 2016-09 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to retained earnings for previously unrecognized tax benefits	$ 1,740
Discrete tax benefit	9,307	$ 0	$ 0
ASU 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to retained earnings for previously unrecognized tax benefits	1,740
Discrete tax benefit	$ 9,307