| Options granted to consultants, directors, and other service providers: |
| Year ended December 31, | ||||||||||||||||||||||||
| 2011 | 2012 | 2013 | ||||||||||||||||||||||
| Weighted | Weighted | Weighted | ||||||||||||||||||||||
| Number | average | Number | average | Number | average | |||||||||||||||||||
| of | exercise | of | exercise | of | exercise | |||||||||||||||||||
| options | price | options | price | options | price | |||||||||||||||||||
| Outstanding at beginning of year | 1,438,692 | $ | 4.697 | 1,238,692 | $ | 5.385 | 912,425 | $ | 7.259 | |||||||||||||||
| Changes during the year-Exercised (*) | 200,000 | 0.001 | 326,267 | 0.12 | ||||||||||||||||||||
| Outstanding at end of year | 1,238,692 | $ | 5.385 | 912,425 | $ | 7.259 | 912,425 | $ | 7.259 | |||||||||||||||
| Exercisable at end of year | 1,235,567 | $ | 5.385 | 912,425 | $ | 7.259 | 912,425 | $ | 7.259 | |||||||||||||||
(*) The total intrinsic value of options exercised during the years ended December 31, 2011 and 2012, was approximately $1.9 million, and $2.3 million, respectively.