Marketable Securities

12 Months Ended

Dec. 31, 2021

Marketable Securities [Abstract]

Marketable Securities

Note 4. Marketable securities

Marketable securities at December 31, 2021 consisted of the following (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Loss			Fair Value
Marketable securities:
Corporate debt securities	$	308,952	$	1	$	(653	)	$	308,300
U.S. government debt securities		37,988		—		(105	)		37,883
U.S. Treasury securities		29,190		—		(18	)		29,172
Total marketable securities, current and non-current	$	376,130	$	1	$	(776	)	$	375,355

Marketable securities at December 31, 2020 consisted of the following (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Loss		Fair Value
Marketable securities
U.S. Treasury securities	$	189,949	$	13	$	—	$	189,962
Total marketable securities, current	$	189,949	$	13	$	—	$	189,962

As of December 31, 2021, the Company held 123 marketable securities, with an aggregate fair value of $365.5 million, in an unrealized loss position. There were no individual securities that were in a significant unrealized loss position as of December 31, 2021, and the Company did not record an allowance for credit losses as of December 31, 2021 related to these

securities. Further, given the lack of significant change in the credit risk of these investments, the Company did not recognize any other-than-temporary impairment losses.