Share Option Plan and ESPP - Schedule of Stock Option Plan (Details)	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Number of options
Number of options, beginning outstanding (in shares) | shares	10,350,810
Number of options, granted (in shares) | shares	671,530
Number of options, exercised (in shares) | shares	(291,088)
Number of options, forfeited and canceled (in shares) | shares	(6,025)
Number of options, ending outstanding (in shares) | shares	10,725,227
Number of options, exercisable options (in shares) | shares	4,572,967
Weighted average exercise price
Weighted average exercise price, beginning outstanding (in usd per share) | $ / shares	$ 20.40
Weighted average exercise price, granted (in usd per share) | $ / shares	69.37
Weighted average exercise price, exercised (in usd per share) | $ / shares	15.52
Weighted average exercise price, forfeited and canceled (in usd per share) | $ / shares	41.39
Weighted average exercise price, ending outstanding (in usd per share) | $ / shares	23.58
Weighted average exercise price, exercisable options (in usd per share) | $ / shares	$ 16.17