COMMON STOCK AND EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
COMMON STOCK AND EARNINGS PER SHARE
Weighted-average number of common shares outstanding - basic	47,200,099	46,833,216
Potentially dilutive shares resulting from stock plans	848,895	739,270
Weighted-average number of common shares outstanding - diluted	48,048,994	47,572,486
Antidilutive equity awards number of shares not included in the weighted-average common shares - diluted	164,000	164,000
Earnings per share, other disclosures
Repurchase of common stock, shares	237,628	133,767
Purchase of common stock for treasury	$ 3,691	$ 2,331
Exercise of stock options, shares	1,590	183,036
Proceeds from the issuance of common stock	$ 36	$ 2,134
Vested (in shares)	496,191	66,630