v3.19.3

STOCKHOLDERS' EQUITY - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Number of Stock Options Outstanding
Beginning balance (in shares)		33,152,881
Granted (in shares)		1,184,657
Exercised (in shares)		(7,881,289)
Forfeited (in shares)		(136,772)
Ending balance (in shares)	26,319,477	26,319,477	33,152,881
Weighted Average Exercise Price
Beginning balance (in USD per share)		$ 9.52
Granted (in USD per share)		72.15
Exercised (in USD per share)		7.97
Forfeited (in USD per share)		11.70
Ending balance (in USD per share)	$ 12.80	$ 9.52	$ 9.52
Options Exercisable
Options exercisable (in shares)	24,136,540
Options exercisable (in USD per share)	$ 9.40
Additional Disclosures
Weighted average remaining contractual term, options outstanding		5 years 2 months 23 days	5 years 5 months 12 days
Weighted average remaining contractual term, options exercisable		4 years 11 months 1 day
Aggregate intrinsic value, options outstanding	$ 1,305,789		$ 1,543,793
Aggregate intrinsic value, options exercisable	$ 1,269,509

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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