SHARE INCENTIVE PLANS: (Details 2) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Dec. 31, 2014
Ordinary shares reserved for future issuance under equity incentive plans
Total shares reserved for future issuance (in shares)			6,800,963
Ordinary Shares
Ordinary shares reserved for future issuance under equity incentive plans
Shares authorized for future issuance (in shares)			1,501,217
RSUs
Activity in nonvested restricted share units outstanding
Non vested restricted share units at the beginning of the period (in shares)	1,911,166
Restricted share units granted (in shares)	1,072,355
Restricted share units vested (in shares)	(485,806)
Restricted share units cancelled (in shares)	(62,322)
Non vested restricted share units at the end of the period (in shares)	2,435,393
Weighted Average Grant Date Fair Value, Restricted Share Units Outstanding
Non vested restricted share units at the beginning of the period (in dollars per share)	$ 41.61
Restricted share units granted (in dollars per share)	46.15	$ 33.22
Restricted share units vested (in dollars per share)	46.35
Restricted share units cancelled (in dollars per share)	42.12
Non vested restricted share units at the end of the period (in dollars per share)	$ 44.09
Total intrinsic value of all outstanding restricted share units			$ 118.3	$ 81.7
Ordinary shares reserved for future issuance under equity incentive plans
Restricted share units outstanding	1,911,166		2,435,393	1,911,166
Share options
Ordinary shares reserved for future issuance under equity incentive plans
Shares outstanding			2,177,867
Employee Share Purchase Plan
Ordinary shares reserved for future issuance under equity incentive plans
Shares authorized for future issuance (in shares)			686,486