v3.19.1
STOCK CAPITAL (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation $ 9,704 $ 6,849
Unrecognized compensation expense 104,122  
General and administrative expenses 11,691 4,753
Options [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Intrinsic value of options exercised $ 788  
Weighted average grant date fair value of options granted $ 19.83  
Stock-based compensation $ 173 $ 529
Options [Member] | SMRE [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Weighted average grant date fair value of options granted $ 40.24  
Number of shares granted 334,096  
General and administrative expenses $ 841  
Maximum [Member] | Option [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of options available for future grant under the plan 10,000,000  
2007 Plan, Transferred to 2015 Plan [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of options available for future grant under the plan 379,358  
2015 Plan [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of options reserved for issuance under the plan 10,383,357  
Number of options available for future grant under the plan 8,686,589  
2015 Plan [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Annual increase percentage 5.00%  
ESPP [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of options reserved for issuance under the plan 2,199,808  
Number of options available for future grant under the plan 1,814,162  
Maximum number of excess shares authorized 487,643  
Number of Common stock purchased 385,646  
Maximum percentage of salary 10.00%  
Maximum amount authorized per person $ 10  
Maximum percentage of common stock 85.00%  
ESPP [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Annual increase percentage 1.00%