Stock-Based Compensation

6 Months Ended

Jun. 30, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Total stock-based compensation expense was recognized in our Condensed Consolidated Statements of Operations as follows (in thousands):



	Three months ended June 30,				Six months ended June 30,
	2019		2018		2019		2018
Cost of goods sold	$	1,086	$	1,163	$	2,089	$	2,294
Research and development	15,430		12,990		31,870		25,084
General and administrative	8,006		6,506		15,948		13,230
Total stock-based compensation	$	24,522	$	20,659	$	49,907	$	40,608

During the three months ended June 30, 2019 and 2018, we granted 95,000 and 528,975 stock options, respectively, and these options had a weighted average grant-date fair value of $17.00 per share and $44.32 per share, respectively. During the six months ended June 30, 2019 and 2018, we granted 115,455 and 738,675 stock options, respectively, and these options had a weighted average grant-date fair value of $18.51 per share and $41.53 per share, respectively. During the three months ended June 30, 2019 and 2018, we granted 262,750 and 396,240 RSUs, respectively. During the six months ended June 30, 2019 and 2018, we granted 395,570 and 406,240 RSUs, respectively, and these RSUs had a weighted average grant-date fair value of $34.85 per share and $53.44 per share, respectively.

As a result of stock issuances under our equity compensation plans, during the three months ended June 30, 2019 and 2018, we issued 738,538 and 1,750,908 shares of our common stock, respectively, and during the six months ended June 30, 2019 and 2018, we issued 1,436,538 and 4,605,724 shares of our common stock, respectively.