MARKETABLE DEBT SECURITIES

6 Months Ended

Jun. 30, 2024

Investments, Debt and Equity Securities [Abstract]

We invest our excess cash balances in marketable debt securities and at each balance sheet date presented, we classify all of our investments in debt securities as available-for-sale and as current assets as they represent the investment of funds available for current operations. We did not record any impairment charges related to our marketable debt securities during the three and six months ended June 30, 2024 or 2023.

The following tables summarize our marketable debt securities:


	As of June 30, 2024
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. treasury securities	$	920,578	$	79	$	(1,671)	$	918,986
U.S. government-sponsored enterprise securities	384,165		63		(727)		383,501
Corporate notes	305,491		39		(527)		305,003
Commercial paper	76,379		—		—		76,379

Municipal securities	5,017		—		(3)		5,014
Total	$	1,691,630	$	181	$	(2,928)	$	1,688,883


	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

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


(In thousands)	As of June 30, 2024		As of December 31, 2023
Marketable debt securities	$	1,646,268	$	1,615,516
Cash and cash equivalents	42,615		34,159
Total	$	1,688,883	$	1,649,675