EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Numerator:
Net income	$ 53,638	$ 68,354
Denominator:
Basic weighted average shares outstanding (in shares)	69,585,000	76,242,000
Effect of dilutive securities - Stock options and awards (in shares)	661,000	817,000
Diluted weighted average shares outstanding (in shares)	70,246,000	77,059,000
Earnings (loss) per share
Basic earnings (loss) per share (in dollars per share)	$ 0.77	$ 0.90
Diluted earnings (loss) per share (in dollars per share)	$ 0.76	$ 0.89
Anti-dilutive shares excluded from the computation of diluted earnings per share	776,600	407,290