Earnings (Loss) per Share (Tables)

12 Months Ended

Dec. 31, 2018

Earnings (Loss) per Share

Schedule of basic and diluted loss per share

	Year ended December 31,
(in thousands, except per share data)	2016		2017		2018
Net loss for the period	$	(54,890)	$	(74,356)	$	(114,780)
Weighted average number of shares outstanding		21,478,320		29,830,669		50,795,768
Basic and diluted loss per share	$	(2.56)	$	(2.49)	$	(2.26)

Schedule of ordinary share equivalents excluded from the calculations of diluted loss per share

	Year ended December 31,
	2016	2017	2018
Stock options	1,904,320	3,338,999	6,091,338
Restricted stock units	—	—	1,372,100