EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Earning per share
Authorized common stock (in shares)	199,000		199,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Income (Numerator)
Income available to common stockholders (in dollars)	$ 51,820	$ 43,863
Shares (Denominator)
Basic (in shares)	62,355	62,722
Total average equivalent shares	64,234	65,063
Per Share Amount
Net income per share, basic (in dollars per share)	$ 0.83	$ 0.70
Net income per share, diluted (in dollars per share)	$ 0.81	$ 0.67
Stock options
Shares (Denominator)
Effect of dilutive stock based compensation (in shares)	1,827	2,299
Restricted stock units
Shares (Denominator)
Effect of dilutive stock based compensation (in shares)	52	42