MARKETABLE DEBT SECURITIES

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

MARKETABLE DEBT SECURITIES

MARKETABLE DEBT SECURITIES

The following tables summarize our marketable debt securities:

	As of December 31, 2023
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. treasury securities	$	892,237	$	1,085	$	(588)	$	892,734
U.S. government-sponsored enterprise securities	440,915		1,000		(574)		441,341
Corporate notes	252,487		945		(320)		253,112
Commercial paper	58,901		—		—		58,901
Certificates of deposit	3,587		—		—		3,587
Total	$	1,648,127	$	3,030	$	(1,482)	$	1,649,675

	As of December 31, 2022
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. treasury securities	$	870,033	$	79	$	(4,382)	$	865,730
U.S. government-sponsored enterprise securities	275,610		24		(3,101)		272,533
Corporate notes	211,398		16		(2,106)		209,308
Commercial paper	59,143		—		—		59,143
Certificates of deposit	4,419		—		—		4,419
Total	$	1,420,603	$	119	$	(9,589)	$	1,411,133

The fair values of our marketable debt securities by classification in the consolidated balance sheets were as follows:

	As of December 31,
(In thousands)	2023		2022
Cash and cash equivalents	$	34,159	$	113,243
Marketable debt securities	1,615,516		1,297,890
Total	$	1,649,675	$	1,411,133