Net Loss Per Common Share (Tables)

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

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

	Three months ended June 30,				Six months ended June 30,
	2017		2016		2017		2016
Weighted average shares outstanding:
Common stock warrants		839,614		706,331		795,490		645,353
Options		2,040,322		2,069,911		2,120,936		2,027,480
Total		2,879,936		2,776,242		2,916,426		2,672,833