SHARE INCENTIVE PLANS: (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2012
Exercise prices range from $ 2.63 to $ 8.23
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 2.63
Exercise price, high end of range (in dollars per share)	$ 8.23
Number of options outstanding (in shares)	390,188
Weighted Average Remaining Contractual Life, Options Outstanding	5 years 3 months 29 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 7.77
Number of exercisable options outstanding (in shares)	387,184
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 7.77
Exercise prices range from $ 8.45 to $ 9.19
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 8.45
Exercise price, high end of range (in dollars per share)	$ 9.19
Number of options outstanding (in shares)	340,168
Weighted Average Remaining Contractual Life, Options Outstanding	4 years 8 months 5 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 9.01
Number of exercisable options outstanding (in shares)	326,966
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 9.03
Exercise prices range from $ 10.23 to $ 10.23
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 10.23
Exercise price, high end of range (in dollars per share)	$ 10.23
Number of options outstanding (in shares)	669,609
Weighted Average Remaining Contractual Life, Options Outstanding	6 years 14 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 10.23
Number of exercisable options outstanding (in shares)	641,076
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 10.23
Exercise prices range from $ 10.50 to $ 18.87
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 10.50
Exercise price, high end of range (in dollars per share)	$ 18.87
Number of options outstanding (in shares)	331,007
Weighted Average Remaining Contractual Life, Options Outstanding	6 years 5 months 23 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 14.37
Number of exercisable options outstanding (in shares)	249,142
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 13.97
Exercise prices range from $ 18.87 to $ 27.72
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 18.97
Exercise price, high end of range (in dollars per share)	$ 27.72
Number of options outstanding (in shares)	349,422
Weighted Average Remaining Contractual Life, Options Outstanding	7 years 5 months 16 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 23.08
Number of exercisable options outstanding (in shares)	154,294
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 23.13
Exercise prices range from $ 29.03 to $ 34.00
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 29.03
Exercise price, high end of range (in dollars per share)	$ 34.00
Number of options outstanding (in shares)	363,133
Weighted Average Remaining Contractual Life, Options Outstanding	8 years 6 months 18 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 31.19
Number of exercisable options outstanding (in shares)	101,665
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 30.83
Exercise prices range from $ 35.12 to $ 66.07
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 35.12
Exercise price, high end of range (in dollars per share)	$ 66.07
Number of options outstanding (in shares)	502,255
Weighted Average Remaining Contractual Life, Options Outstanding	9 years 1 month 2 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 52.98
Number of exercisable options outstanding (in shares)	27,439
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 35.12
Exercise prices range from $ 79.38 to $ 79.38
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 79.38
Exercise price, high end of range (in dollars per share)	$ 79.38
Number of options outstanding (in shares)	26,700
Weighted Average Remaining Contractual Life, Options Outstanding	9 years 9 months 29 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 79.38
Exercise prices range from $ 101.37 to $ 101.37
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 101.37
Exercise price, high end of range (in dollars per share)	$ 101.37
Number of options outstanding (in shares)	313,290
Weighted Average Remaining Contractual Life, Options Outstanding	9 years 7 months 10 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 101.37
Exercise prices range from $ 1003.13 to $ 1003.13
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 1,003.13
Exercise price, high end of range (in dollars per share)	$ 1,003.13
Number of options outstanding (in shares)	150
Weighted Average Remaining Contractual Life, Options Outstanding	4 months 24 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 1,003.13
Number of exercisable options outstanding (in shares)	150
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 1,003.13
Exercise prices range from $ 2.63 to $ 1003.13
Additional information about options outstanding and exercisable
Exercise price, low end of range (in dollars per share)	$ 2.63
Exercise price, high end of range (in dollars per share)	$ 1,003.13
Number of options outstanding (in shares)	3,285,922
Weighted Average Remaining Contractual Life, Options Outstanding	7 years 1 month 13 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 29.74
Number of exercisable options outstanding (in shares)	1,887,916
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 12.62