Marketable Securities

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Marketable securities as of December 31, 2023 and 2022 consist of both available-for-sale debt securities of investment grade issuers (see below and Note 5) as well as equity securities of publicly traded companies (see Note 5).

The following tables summarize the Company's investments in available-for-sale debt securities:


(In millions)	Amortized		Unrealized				Fair
As of December 31, 2023	Cost Basis		Gains		Losses		Value
Corporate bonds	$	6,492.5	$	10.4	$	(104.9)	$	6,398.0
U.S. government and government agency obligations	4,839.6		2.4		(8.6)		4,833.4
Sovereign bonds	58.1		—		(0.9)		57.2
Commercial paper	636.8		0.2		(0.2)		636.8
Certificates of deposit	520.8		0.6		—		521.4
Asset-backed securities	88.2		0.1		(1.2)		87.1
	$	12,636.0	$	13.7	$	(115.8)	$	12,533.9

As of December 31, 2022
Corporate bonds	$	6,975.5	$	—	$	(291.1)	$	6,684.4
U.S. government and government agency obligations	2,945.4		0.9		(6.9)		2,939.4
Sovereign bonds	67.1		—		(3.0)		64.1
Commercial paper	121.1		—		—		121.1
Certificates of deposit	182.1		—		(0.1)		182.0
Asset-backed securities	28.9		—		(1.7)		27.2
	$	10,320.1	$	0.9	$	(302.8)	$	10,018.2

The Company classifies its investments in available-for-sale debt securities based on their contractual maturity dates. The available-for-sale debt securities as of December 31, 2023 mature at various dates through April 2029. The fair values of available-for-sale debt securities by contractual maturity consist of the following:


	As of December 31,
(In millions)	2023		2022
Maturities within one year	$	8,114.8	$	4,636.4
Maturities after one year through five years	4,414.5		5,381.4
Maturities after five years	4.6		0.4
	$	12,533.9	$	10,018.2

The following table shows the fair value of the Company's available-for-sale debt securities that have unrealized losses, aggregated by investment category and length of time that the individual securities have been in a continuous loss position.


	Less than 12 Months				12 Months or Greater				Total
(In millions) As of December 31, 2023	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Corporate bonds	$	2,363.3	$	(2.4)	$	4,034.7	$	(102.5)	$	6,398.0	$	(104.9)
U.S. government and government agency obligations	4,780.6		(6.0)		52.7		(2.6)		4,833.3		(8.6)
Sovereign bonds	12.4		(0.1)		44.8		(0.8)		57.2		(0.9)
Commercial paper	636.8		(0.2)		—		—		636.8		(0.2)
Asset-backed securities	61.8		(0.3)		25.3		(0.9)		87.1		(1.2)
	$	7,854.9	$	(9.0)	$	4,157.5	$	(106.8)	$	12,012.4	$	(115.8)

As of December 31, 2022
Corporate bonds	$	2,445.4	$	(73.1)	$	4,200.4	$	(218.0)	$	6,645.8	$	(291.1)
U.S. government and government agency obligations	785.2		(2.0)		71.0		(4.9)		856.2		(6.9)
Sovereign bonds	18.6		(1.1)		45.6		(1.9)		64.2		(3.0)
Certificates of deposit	40.2		(0.1)		—		—		40.2		(0.1)
Asset-backed securities	11.5		(0.6)		15.2		(1.1)		26.7		(1.7)
	$	3,300.9	$	(76.9)	$	4,332.2	$	(225.9)	$	7,633.1	$	(302.8)

The unrealized losses on corporate bonds as of December 31, 2023 and 2022 were primarily driven by increased interest rates. The Company has reviewed its portfolio of available-for-sale debt securities and determined that the decline in fair value below cost did not result from credit-related factors. In addition, the Company does not intend to sell, and it is not more likely than not that the Company will be required to sell, such securities before recovery of their amortized cost bases.

With respect to marketable securities, for the years ended December 31, 2023, 2022, and 2021, amounts reclassified from Accumulated other comprehensive loss into Other income (expense), net were related to realized gains/losses on sales of available-for-sale debt securities. Realized gains and losses on sales of marketable securities were not material for the years ended December 31, 2023, 2022, and 2021.

The Company recognized interest income of $495.9 million, $160.1 million, and $45.8 million for the years ended December 31, 2023, 2022, and 2021, respectively, in Other income (expense), net.