Significant Events and Transactions of the Period - Summary of Restructuring Reserve (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Closing R&D Operations In Palo Alto
Restructuring Reserve [Roll Forward]
Beginning balance		$ 5,581
Restructuring costs	$ 50	497
Restructuring costs - non cash item		0
Amount paid		(5,030)
Ending balance	1,048	1,048
New Organization Structure
Restructuring Reserve [Roll Forward]
Beginning balance		510
Restructuring costs	400	1,133
Amount paid		(1,529)
Ending balance	$ 114	$ 114