EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Options to purchase shares	2,600,000	381,000	2,200,000	381,000
Net income	$ 7,973	$ 9,454	$ 15,048	$ 18,073
Weighted average shares outstanding-basic	57,833,000	62,640,000	57,682,000	63,379,000
Shares issuable upon exercise of stock options	3,077,000	3,364,000	3,320,000	3,496,000
Weighted average shares outstanding-diluted	60,910,000	66,004,000	61,002,000	66,875,000
Basic earnings per share	$ 0.14	$ 0.15	$ 0.26	$ 0.29
Diluted earnings per share	$ 0.13	$ 0.14	$ 0.25	$ 0.27