Marketable Securities and Equity Investments (Tables)

12 Months Ended

Dec. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Schedule of Cash Equivalents and Marketable Securities

A summary of our cash equivalents and marketable securities, which are recorded at fair value, is shown below:

	As of December 31, 2024								As of December 31, 2023
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
	(in millions)
Cash equivalents	$	1,687.1	$	—	$	—	$	1,687.1	$	7,033.9	$	—	$	—	$	7,033.9
Marketable securities:
U.S. Treasury securities	$	1,603.9	$	3.6	$	(5.5)	$	1,602.0	$	544.5	$	3.0	$	(1.0)	$	546.5
U.S. government agency securities	240.5		0.5		(0.5)		240.5		424.8		0.9		(0.5)		425.2
Asset-backed securities	1,239.6		5.1		(0.5)		1,244.2		304.9		1.4		(0.3)		306.0
Certificates of deposit	—		—		—		—		33.7		0.0		(0.0)		33.7
Corporate debt securities	3,519.4		10.6		(4.1)		3,525.9		1,794.0		10.5		(1.7)		1,802.8
Commercial paper	5.0		0.0		(0.0)		5.0		186.8		0.1		(0.1)		186.8
Total marketable available-for-sale debt securities	6,608.4		19.8		(10.6)		6,617.6		3,288.7		15.9		(3.6)		3,301.0
Corporate equity securities	72.1		3.0		(38.5)		36.6		72.1		—		(26.1)		46.0
Total marketable securities	6,680.5		22.8		(49.1)		6,654.2		3,360.8		15.9		(29.7)		3,347.0
Total cash equivalents and marketable securities	$	8,367.6	$	22.8	$	(49.1)	$	8,341.3	$	10,394.7	$	15.9	$	(29.7)	$	10,380.9

Amounts in the table above at fair value were classified on our consolidated balance sheets as follows:

	December 31,
	2024		2023
	(in millions)
Cash and cash equivalents	$	1,687.1	$	7,033.9
Marketable securities	1,546.3		849.2
Long-term marketable securities	5,107.9		2,497.8
Total	$	8,341.3	$	10,380.9

Marketable available-for-sale debt securities by contractual maturity were as follows:

	December 31,
	2024		2023
	(in millions)
Matures within one year	$	1,509.7	$	803.2
Matures after one year through five years	5,034.4		2,495.6
Matures after five years	73.5		2.2
Total	$	6,617.6	$	3,301.0

Schedule of Company's Net Unrealized (Losses) Gains on Corporate Equity Securities

During the three years ended December 31, 2024, our net unrealized losses on corporate equity securities with readily determinable fair values held at the conclusion of each period were as follows:

	Year ended December 31,
	2024		2023		2022
	(in millions)
Net unrealized losses	$	(9.5)	$	(7.5)	$	(149.1)