COMMON STOCK Stocked Based Compensation Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 19,502	$ 20,068	$ 17,518
Income tax benefit	(7,296)	(7,636)	(5,955)
Net stock-based compensation expense	$ 12,206	$ 12,432	$ 11,563