Earnings (Loss) per Share (Tables)

3 Months Ended

Mar. 31, 2018

Earnings (Loss) per Share

Schedule of basic and diluted loss per share

	Three Months Ended March 31,
(in thousands, except per share data)	2017			2018
Net loss for the period	$	(15,223	)	$	(13,342	)
Weighted average number of shares outstanding	27,204,230			36,911,604
Basic and diluted loss per share	$	(0.56	)	$	(0.36	)

Schedule of common stock equivalents excluded from the calculations of diluted loss per share

	Three Months Ended
	March 31,
(in thousands)	2017	2018
Stock options	278,579	4,853,349
Restricted stock units	—	339,550