Marketable Securities

3 Months Ended

Mar. 31, 2021

Marketable Securities [Abstract]

Marketable Securities

Note 4. Marketable securities

Marketable securities as of March 31, 2021 consisted of the following:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Marketable securities:
Corporate debt securities	$	161,109	$	1	$	(103	)	$	161,007
U.S. Treasury securities		84,988		8		—			84,996
U.S. government debt securities		5,059		—		—			5,059
Total marketable securities, current and non-current	$	251,156	$	9	$	(103	)	$	251,062

Marketable securities as of December 31, 2020 consisted of the following:

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

As of March 31, 2021, the Company held 52 marketable securities, with an aggregate fair value of $135.4 million, in an unrealized loss position. There were no individual securities that were in a significant unrealized loss position as of March 31, 2021 and the Company did not record an allowance for credit losses as of March 31, 2021 related to these securities. Further, given the short-term duration and the lack of significant change in the credit risk of these investments, the Company did not recognize any other-than-temporary impairment losses.