EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Numerator:
Net income	$ 45,689	$ 66,044	$ 179,474	$ 205,456
Denominator:
Basic weighted average shares outstanding (in shares)	78,817,000	81,644,000	79,779,000	82,260,000
Effect of dilutive securities - Stock options and awards (in shares)	908,000	1,063,000	923,000	1,054,000
Diluted weighted average shares outstanding (in shares)	79,725,000	82,707,000	80,702,000	83,314,000
Earnings (loss) per share
Basic earnings per share (in dollars per share)	$ 0.58	$ 0.81	$ 2.25	$ 2.50
Diluted earnings per share (in dollars per share)	$ 0.57	$ 0.80	$ 2.22	$ 2.47
Anti-dilutive shares excluded from the computation of diluted earnings per share	259,336	44,026	260,964	420,584