EQUITY
 12 Months Ended
Dec. 31, 2016
Stockholders' Equity Note [Abstract]  
EQUITY
NOTE 8   EQUITY
Share capital
a.       As of December 31, 2016, the Company’s issued share capital was comprised of ordinary shares, €0.01 par value. The ordinary shares confer upon the holders the right to receive notice to participate and vote in shareholders meetings of the Company and to receive dividend, if and when declared.
 
b.       On August 6, 2014, the Company completed its IPO. In connection with the IPO, all then outstanding share classes were converted to ordinary shares on a one-for-one basis. For additional information see Note 1.
 
c.       In July 2014, the Company’s shareholders approved a five-for-one stock split of all classes of the Company’s shares. All of the share and per share amounts have been adjusted, on a retroactive basis, to reflect this stock split.
 
In addition, in July 2014, the Company’s Articles were amended to convert all classes of shares into one class of ordinary shares on a one-for-one basis and the Company’s shareholders approved an increase in the number of authorized shares to 1,012,565,725 ordinary shares.
Following is a summary of the equity activity for the years ended December 31, 2016, 2015 and 2014:
​ ​ ​
Ordinary 
Shares
 ​ ​
Class A 
Ordinary 
Shares
 ​ ​
Class B 
Ordinary 
Shares
 ​ ​
Class C 
Ordinary 
Shares
 ​ ​
Class D 
Ordinary 
Shares
 ​ ​
Class E 
Ordinary 
Shares
 ​ ​
Class F1 
Ordinary 
Shares
 ​ ​
Class F2 
Ordinary 
Shares
 ​ ​
Ordinary 
Shares (with 
liquidation 
preference)
 ​
​ ​ ​
Number of shares – issued and outstanding
 ​
Balance, as of January 1, 2014
 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 32,070,835 ​ ​ ​ ​ ​ 6,703,520 ​ ​ ​ ​ ​ 3,390,490 ​ ​ ​ ​ ​ 32,164,955 ​ ​ ​ ​ ​ 11,749,700 ​ ​ ​ ​ ​ 14,326,650 ​ ​ ​ ​ ​ 41,547,280 ​ ​ ​ ​ ​ 60,559,715 ​ ​
Exercise of options – prior to IPO
 ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ 1,463,051 ​ ​
Conversion upon IPO closing
 ​ ​ ​ ​ 203,976,196 ​ ​ ​ ​ ​ (32,070,835) ​ ​ ​ ​ ​ (6,703,520) ​ ​ ​ ​ ​ (3,390,490) ​ ​ ​ ​ ​ (32,164,955) ​ ​ ​ ​ ​ (11,749,700) ​ ​ ​ ​ ​ (14,326,650) ​ ​ ​ ​ ​ (41,547,280) ​ ​ ​ ​ ​ (62,022,766) ​ ​
IPO
 ​ ​ ​ ​ 8,325,000 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Exercise of options – commencing IPO
 ​ ​ ​ ​ 2,252,865 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Balance, as of December 31, 2014
 ​ ​ ​ ​ 214,554,061 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Exercise of options and vesting of RSUs
 ​ ​ ​ ​ 4,293,369 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Balance, as of December 31, 2015
 ​ ​ ​ ​ 218,847,430 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Exercise of options and vesting of RSUs
 ​ ​ ​ ​ 2,890,584 ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ — ​ ​
Balance, as of December 31, 2016
 ​ ​ ​ ​ 221,738,014 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
​
 
d. Employee and Non-employee equity awards
(i) Description of plans and taxation
The Company has adopted a stock option plan (the “2003 Plan”), whereby options exercisable for ordinary shares representing up to 11% of the Company’s total issued and outstanding shares may be granted to employees and service providers. In May 2014, the Company increased the pool of options available under the 2003 Plan to up to 18% of the total issued and outstanding shares of the Company. Under the terms of the 2003 Plan, the board of directors or the designated committee will grant options, determine the vesting period over which options become exercisable and determine the exercise terms.
In December 2014, the board of directors approved and the Company adopted its 2014 Equity Incentive Plan (the “2014 Plan”). Under the 2014 Plan, the board of directors or its designated committee will grant share options, restricted shares and restricted share units (“RSUs”). The total number of ordinary shares available under both the 2003 Plan and the 2014 Plan may not exceed 38,619,123.
Under both plans, the Company usually grants options that vest over a period of 4 – 4.5 years and expire 7 years after grant and under the 2014 Plan for RSUs that vest over a period of three years. Each option can be exercised for one ordinary share EUR 0.01 par value of the Company.
No additional awards are expected to be granted under the 2003 Plan.
With respect to Israeli employees, both plans are intended to be governed by the terms stipulated by Section 102 of the Israeli Income Tax Ordinance. In accordance with the capital gain track chosen by the Company and pursuant to the terms thereof, the Company is not allowed to claim, as an expense for tax purposes, the amounts credited to employees as a benefit, including amounts recorded as salary benefits in the Company’s financial statements, in respect of equity granted to employees under the Plans — with the exception of the work-income benefit component, if any, determined on the grant date.
(ii) Options
The following table summarizes information regarding outstanding and exercisable options under the Company’s plans as of December 31, 2016:
 
Exercise price
    
Outstanding
    
Exercisable
  
 
(US $)
    
Number
    
Weighted average
remaining
contractual life
(in years)
    
Number
    
Weighted average
remaining
contractual life
(in years)
  
 
0.096 – 2.991
         119,655           3.35           84,655           3.48    
 
3.7
         5,882,283           2.84           5,734,118           2.85    
 
6.98
         13,146,059           4.06           12,227,784           4.03    
 
25 – 46.88
         5,384,240           6.35           238,356           5.06    
 
55.63 – 59.33
         4,410,700           5.68           1,470,350           5.68    
            28,942,937           4.48           19,755,263           3.82    
 
The following table summarizes the option activity for the year ended December 31, 2016 for options granted to employees, directors and service providers:
     
Number
    
Weighted
average
exercise price
    
Aggregated
intrinsic value(1)
  
                 
$
    
U.S. dollars
in thousands
  
Options outstanding at beginning of year
         27,188,687           14.85                
Changes during the year:        
Granted(2)
         4,576,500           45.91                
Exercised
         (2,746,100)           2.88                
Forfeited
         (76,150)           18.90                
Options outstanding at end of year
         28,942,937           20.82           623,550    
Options exercisable at year-end
         19,755,263           10.05           583,398    
 
 
(1)    The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying awards and the closing stock price of  $38.12 of the Company’s ordinary share on December 31, 2016. This represents the potential pre-tax amount receivable by the option holders had all option holders exercised their options as of such date.
 
(2)    On August 15, 2016 the Company granted the Company’s founders, who are also shareholders, 4,000,000 options, exercisable into the same amount of the Company’s ordinary shares, at an exercise price of  $46.88 per share, which are subject to graded vesting over four years.
 
On September 6, 2015 the Company granted the Company’s founders, who are also shareholders, 4,400,000 options, exercisable into the same amount of the Company’s ordinary shares, at an exercise price of  $57.58 per share, which are subject to graded vesting over three years.
 
At December 31, 2016, there were 51,000 options outstanding with a weighted average exercise price of $20.05 and weighted average remaining contractual life of 3.54 years, which were granted to service providers. At December 31, 2016, 27,250 of these options were exercisable.
(iii) RSUs
The following table summarizes RSU activity for the year ended December 31, 2016 for RSUs granted:
     
Number
    
Weighted average
grant date fair value ($)
  
Outstanding at beginning of year
         281,181           41.0    
Changes during the year:      
Granted
         205,962           38.96    
Vested
         (144,484)           40.33    
Forfeited
         (16,372)           41.07    
Outstanding at end of year
         326,287           40.01    
 
(iv) Valuation
The fair value of options granted was estimated using the Black-Scholes option pricing model, and based on the following assumptions:
     
Year ended December 31,
  
     
2016
    
2015
    
2014
  
Risk-free interest rate
    
0.93% – 1.57% 
    
0.75% – 2.01% 
    
0.7% – 2.17% 
  
Expected option term
    
3.28 – 6.67 years 
    
2.16 – 6.95 years 
    
3.82 – 7.27 years 
  
Expected price volatility
    
40% – 44% 
    
35% – 53% 
    
36% – 55% 
  
Dividend yield
    
0% 
    
0% 
    
0% 
  
Weighted average fair value at the date of grant
    
$17.09 
    
$16.05 
    
$7.28 
  
•       The interest rate for periods within the contractual life of the award is based on the U.S. Treasury yield curve in effect at the time of grant.
 
•       The Company’s computation of expected volatility was based on a blend of comparable companies and the Company’s stock.
 
•       The expected option term for options awards that were at the money when granted (plain vanilla options) was calculated in accordance with the simplified method in accordance with ASC 718, as adequate historical experience is not available to provide a reasonable estimate. The simplified method will continue to apply until enough historical experience is available to provide a reasonable estimate of the expected term. The expected term of options granted to non-employee service providers is based on the contractual life.
 
•       The Company has historically not paid dividends and does not expect to pay dividends in the near future.
 
The fair value of each RSU awarded is determined based on the market price of the ordinary shares on the date of grant.
(v) Share based compensation expenses summary
Expenses recognized
Share-based compensation expenses included in the Company’s Statements of Operations were:
     
Year ended December 31,
  
     
2016
    
2015
    
2014
  
     
U.S. dollars in thousands
  
Cost of revenues
         46           26           27    
Research and development, net
         12,216           8,016           6,130    
Sales and marketing
         706           1,277           5,201    
General and administrative
         52,634           35,650           65,495    
Total stock-based compensation
         65,602           44,969           76,853    
 
In connection with the closing of the IPO and in accordance with their original terms, the vesting period for certain options were accelerated such that options to purchase 4,950,000 ordinary shares vested and became exercisable upon the closing of the IPO. Out of 4,950,000 options, options to purchase 3,375,000 ordinary shares were granted to the Company’s founders, who are also shareholders. The acceleration resulted in compensation expense of  $6.6 million that was recorded during the year ended December 31, 2014 and included in the above table.
Unrecognized expenses
As of December 31, 2016, there was approximately $99.6 million of total unrecognized compensation expense related to unvested share-based compensation grants, of which $92.4 million related to non-vested options and $7.2 million related to non-vested RSUs. That cost is expected to be recognized over a weighted-average period of 2.15 years.
e. Computation of earnings (losses) per share
The following table sets forth the computation of basic and diluted net earnings (losses) per share:
     
Year ended December 31,
  
     
2016
    
2015
    
2014
  
     
U.S. dollars in thousands, except per share data
  
Numerator for basic and diluted net earnings (losses) per share:
        
Net income (loss) applicable to ordinary shares
         108,370           68,450           (30,084)    
Weighted average shares outstanding:        
Denominator for basic net earnings per share
         220,124           217,362           107,942    
Effect of dilutive securities:        
Employee and Non-Employee stock options and unvested RSUs
         17,894           20,495           —    
Denominator for diluted net earnings per share
         238,018           237,857           107,942    
Basic net earnings (losses) per share
         0.49           0.31           (0.28)    
Diluted net earnings (losses) per share
         0.46           0.29           (0.28)    
Dilutive EPS calculation for the year ended December 31, 2016 and 2015 excludes 7,252 and 2,641 thousand, respectively, outstanding equity awards to purchase ordinary shares because these equity awards have exercise prices in excess of the average market price for the period and therefore the effect of including these equity awards would be antidilutive.
For the year ended December 31, 2014 there was no variance between basic and diluted losses per share because any potentially dilutive securities would have been anti-dilutive due to a basic loss per share. Because of the net loss in 2014, 28,200 thousand of otherwise dilutive stock options were not included in the calculation of diluted EPS for 2014. Additionally, dilutive EPS calculation for 2014 excludes 625 thousand of outstanding options to purchase ordinary shares because these options have exercise prices in excess of the average market price for the period and therefore the effect of including these options would be antidilutive.
Prior to the Company’s IPO in August 2014, the Company had no potentially dilutive instruments since all classes of preferred shares were not convertible into Class A shares, as well as stock based compensation options.