STOCK-BASED COMPENSATION

3 Months Ended

Mar. 31, 2020

Share-based Payment Arrangement [Abstract]

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION

The Company’s stock-based compensation generally includes stock options, restricted stock units (RSUs), performance share units (PSUs), and purchases under the Company’s employee stock purchase plan (ESPP).

The following table presents stock‑based compensation expense recognized in the Company’s Consolidated Statements of Comprehensive Income (in thousands):

	Three Months Ended March 31,
	2020		2019
Cost of sales	$	23	$	—
Research and development expense	163		273
Selling, general and administrative expense	1,748		2,429
Restructuring	—		—
Total	$	1,934	$	2,702

At March 31, 2020, the Company had $0.9 million of total unrecognized compensation expense related to stock option grants that will be recognized over an average vesting period of 1.22 years and $14.6 million of total unrecognized compensation expense related to RSUs and PSUs that will be recognized over an average vesting period of 2.24 years.

During the three months ended March 31, 2020 the Company granted 3.6 million RSUs at an average fair market value of $1.05 per share. The Company did not grant any PSUs or options during three months ended March 31, 2020.