Marketable Securities

12 Months Ended

Dec. 31, 2022

The amortized cost, unrealized gain (loss), and estimated fair value of the Company's investments in securities available for sale consisted of the following:


	December 31, 2022
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value
Marketable securities
U.S. treasury securities	$	384,951	$	—	$	(6,949)	$	378,002
U.S. agency securities	29,012		47		—		29,059
Commercial paper	28,815		—		—		28,815

Corporate debt securities	5,049		—		(67)		4,982
Total marketable securities	$	447,827	$	47	$	(7,016)	$	440,858


	December 31, 2021
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value
Marketable securities
U.S. treasury securities	$	420,392	$	—	$	(2,107)	$	418,285
Commercial paper	13,878		—		—		13,878
Asset-backed securities	2,003		—		(1)		2,002
Corporate debt securities	18,731		3		(24)		18,710
Total marketable securities	$	455,004	$	3	$	(2,132)	$	452,875

The Company had thirteen and nineteen separate marketable securities in unrealized loss positions as of December 31, 2022 and 2021, respectively. The Company does not intend to sell any marketable securities that have an unrealized losses at December 31, 2022 and it is not more likely than not that the Company will be required to sell such securities before any anticipated recovery.

There were no material realized gains or losses from marketable securities that were reclassified out of accumulated other comprehensive income for the year ended December 31, 2022. For marketable securities that have unrealized losses, the Company evaluated whether (i) the Company has the intention to sell any of these investments, (ii) it is not more likely than not that the Company will be required to sell any of these available-for-sale debt securities before recovery of the entire amortized cost basis and (iii) the decline in the fair value of the investment is due to credit or non-credit related factors. Based on this evaluation, the Company determined that for its marketable securities, there were no material credit or non-credit related impairments as of December 31, 2022.

The Company did not identify any marketable securities that were other-than-temporarily impaired as of December 31, 2021.

The following table summarizes the stated maturities of the Company’s marketable securities:


	December 31, 2022				December 31, 2021
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value

Due within one year	$	447,827	$	440,858	$	64,914	$	64,879
Due after one year through two years	—		—		390,090		387,996
Total	$	447,827	$	440,858	$	455,004	$	452,875