MARKETABLE DEBT SECURITIES

3 Months Ended

Mar. 31, 2024

Investments, Debt and Equity Securities [Abstract]

The Company's marketable debt securities as of March 31, 2024 and December 31, 2023 were composed of available-for-sale commercial paper and corporate and government debt securities. The primary objective of the Company’s investment portfolio is to preserve capital and liquidity while enhancing overall returns. The Company’s investment policy limits interest-bearing security investments to certain types of instruments issued by institutions with primarily investment grade credit ratings and places restrictions on maturities and concentration by asset class and issuer.

Marketable debt securities consisted of the following (in thousands):


	March 31, 2024		December 31, 2023
Marketable debt securities:
Commercial paper	$	9,899	$	34,458
Corporate debt securities	304,771		368,323
Securities of government sponsored entities	83,123		105,894
Total available-for-sale marketable debt securities	$	397,793	$	508,675

The following is a summary of short-term marketable debt securities classified as available-for-sale as of March 31, 2024 (in thousands):


	Remaining Contractual Maturity (in years)	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Estimated Fair Value
Marketable debt securities:
Commercial paper	Less than 1	$	9,902	$	—	$	(3)	$	9,899
Corporate debt securities	Less than 1	148,618		47		(328)		148,337
Securities of government-sponsored entities	Less than 1	83,351		29		(257)		83,123
Total maturity less than 1 year		241,871		76		(588)		241,359
Corporate debt securities	1 to 2	156,245		364		(175)		156,434

Total maturity 1 to 2 years		156,245		364		(175)		156,434
Total available-for-sale marketable debt securities		$	398,116	$	440	$	(763)	$	397,793

The following is a summary of short-term marketable debt securities classified as available-for-sale as of December 31, 2023 (in thousands):


	Remaining Contractual Maturity (in years)	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Estimated Fair Value
Marketable debt securities:
Commercial paper	Less than 1	$	34,450	$	25	$	(17)	$	34,458
Corporate debt securities	Less than 1	133,463		29		(408)		133,084
Securities of government-sponsored entities	Less than 1	81,334		36		(274)		81,096
Total maturity less than 1 year		249,247		90		(699)		248,638
Corporate debt securities	1 to 2	233,969		1,444		(174)		235,239
Securities of government-sponsored entities	1 to 2	24,718		106		(26)		24,798
Total maturity 1 to 2 years		258,687		1,550		(200)		260,037
Total available-for-sale securities		$	507,934	$	1,640	$	(899)	$	508,675

For the three months ended March 31, 2024 and 2023, realized gains on marketable debt securities were immaterial. As of March 31, 2024 and December 31, 2023, the accrued interest receivable related to the Company's marketable debt securities was $3.8 million and $4.6 million, respectively, and was recorded in prepaid expenses and other current assets on the Consolidated Balance Sheets.

The Company reviews the available-for-sale marketable debt securities for declines in fair value below the cost basis each quarter. For any security whose fair value is below its amortized cost basis, the Company first evaluates whether it intends to sell the impaired security, or will otherwise be more likely than not required to sell the security before recovery. If either are true, the amortized cost basis of the security is written down to its fair value at the reporting date. If neither circumstance holds true, the Company assesses whether any portion of the unrealized loss is a result of a credit loss. Any amount deemed to be attributable to credit loss is recognized in the income statement, with the amount of the loss limited to the difference between fair value and amortized cost and recorded as an allowance for credit losses. The portion of the unrealized loss related to factors other than credit losses is recognized in other comprehensive income (loss).

The following is a summary of available-for-sale marketable debt securities in an unrealized loss position with no credit losses reported as of March 31, 2024 (in thousands):


	Less Than 12 Months				12 Months or Greater				Total
Description of Securities	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Commercial paper	$	9,899	$	3	$	—	$	—	$	9,899	$	3
Corporate debt securities	112,935		379		30,860		124		143,795		503
Securities of government-sponsored entities	27,224		67		36,037		190		63,261		257
Total	$	150,058	$	449	$	66,897	$	314	$	216,955	$	763

The following is a summary of available-for-sale marketable debt securities in an unrealized loss position with no credit losses reported as of December 31, 2023 (in thousands):


	Less Than 12 Months				12 Months or Greater				Total
Description of Securities	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Commercial paper	$	24,798	$	17	$	—	$	—	$	24,798	$	17
Corporate debt securities	140,802		405		28,775		177		169,577		582
Securities of government-sponsored entities	61,933		217		12,540		83		74,473		300
Total	$	227,533	$	639	$	41,315	$	260	$	268,848	$	899

As of March 31, 2024 and December 31, 2023, the amortized cost of the available-for-sale marketable debt securities in an unrealized loss position was $217.7 million and $269.7 million, respectively.

As of March 31, 2024 and December 31, 2023, the Company does not intend to sell these investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis. The increase in unrealized losses for the three months ended March 31, 2024 was primarily due to fluctuations in short-term interest rates. The Company does not believe the unrealized losses incurred during the period are due to credit-related factors. The credit ratings of the securities held remain of the highest quality. Moreover, the Company continues to receive payments of interest and principal as they become due, and our expectation is that those payments will continue to be received timely. Factors unknown to us at this time may cause actual results to differ and require adjustments to the Company’s estimates and assumptions in the future.