Net Loss Per Common Share (Tables)

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Schedule of anti-dilutive shares

The following table presents anti-dilutive shares for the years ended December 31, 2017, 2016 and 2015 (in thousands):

	2017	2016	2015
Weighted-average anti-dilutive shares related to:
Outstanding stock options	5,671	6,569	4,148
Restricted stock awards	1,064	1,202	519