STOCK-BASED COMPENSATION (Details 4) (Stock options, USD $)	3 Months Ended
	Mar. 31, 2013
Stock options outstanding and exercisable by range of exercise prices
Options Outstanding at the end of the period (in shares)	1,058,985
Options Outstanding - Weighted Average Remaining Contractual Term	5 years 5 months 23 days
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 8.99
Options Exercisable at the end of the period (in shares)	266,554
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 11.88
Range of exercise price $0.01 to $4.99
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 0.01
Exercise price, high end of the range (in dollars per share)	$ 4.99
Options Outstanding at the end of the period (in shares)	914
Options Outstanding - Weighted Average Remaining Contractual Term	6 months 4 days
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 2.54
Options Exercisable at the end of the period (in shares)	914
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 2.54
Range of exercise price $5.00 to $7.45
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 5.00
Exercise price, high end of the range (in dollars per share)	$ 7.45
Options Outstanding at the end of the period (in shares)	304,352
Options Outstanding - Weighted Average Remaining Contractual Term	8 years 5 months 16 days
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 6.65
Options Exercisable at the end of the period (in shares)	101,771
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 6.65
Range of exercise price $7.46 to $9.99
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 7.46
Exercise price, high end of the range (in dollars per share)	$ 9.99
Options Outstanding at the end of the period (in shares)	614,075
Options Outstanding - Weighted Average Remaining Contractual Term	4 years 9 months 7 days
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 8.44
Options Exercisable at the end of the period (in shares)	24,225
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 7.53
Range of exercise price $10.00 to $14.99
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 10.00
Exercise price, high end of the range (in dollars per share)	$ 14.99
Options Outstanding at the end of the period (in shares)	12,201
Options Outstanding - Weighted Average Remaining Contractual Term	1 year 6 months
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 12.33
Options Exercisable at the end of the period (in shares)	12,201
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 12.33
Range of exercise price $15.00 to $19.99
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 15.00
Exercise price, high end of the range (in dollars per share)	$ 19.99
Options Outstanding at the end of the period (in shares)	80,780
Options Outstanding - Weighted Average Remaining Contractual Term	2 years 2 months 1 day
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 15.02
Options Exercisable at the end of the period (in shares)	80,780
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 15.02
Range of exercise price $20.00 to $24.99
Stock options outstanding and exercisable by range of exercise prices
Exercise price, low end of the range (in dollars per share)	$ 20.00
Exercise price, high end of the range (in dollars per share)	$ 24.99
Options Outstanding at the end of the period (in shares)	46,663
Options Outstanding - Weighted Average Remaining Contractual Term	2 years 2 months 8 days
Options Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 20.19
Options Exercisable at the end of the period (in shares)	46,663
Options Exercisable - Weighted Average Exercise Price (in dollars per share)	$ 20.19