Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Summary of financial assets with maturities of less than 90 days included within cash and cash equivalents

The following table summarizes our financial assets with maturities of less than 90 days from the date of purchase included in cash and cash equivalents in our condensed consolidated balance sheets:

(In millions)	As of March 31, 2023		As of December 31, 2022
Commercial paper	$	64.0	$	177.2
Overnight reverse repurchase agreements	300.3		59.0
Money market funds	2,042.3		2,581.5
Short-term debt securities	—		29.9
Total	$	2,406.6	$	2,847.6

Marketable debt and equity securities

The following tables summarize our marketable debt and equity securities, classified as available-for-sale:

	As of March 31, 2023
(In millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable debt securities
Corporate debt securities:
Current	$	1,287.6	$	0.1	$	(4.4)	$	1,283.3
Non-current	423.4		1.0		(3.5)		420.9
Government securities:
Current	863.5		0.1		(4.2)		859.4
Non-current	426.1		1.0		(1.5)		425.6
Mortgage and other asset backed securities:
Current	0.4		—		—		0.4
Non-current	132.9		0.1		(1.3)		131.7
Total marketable debt securities	$	3,133.9	$	2.3	$	(14.9)	$	3,121.3
Marketable equity securities
Marketable equity securities, current	$	87.7	$	—	$	(19.8)	$	67.9
Marketable equity securities, non-current	1,001.1		—		(390.9)		610.2
Total marketable equity securities	$	1,088.8	$	—	$	(410.7)	$	678.1

	As of December 31, 2022
(In millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable debt securities
Corporate debt securities:
Current	$	936.2	$	—	$	(4.9)	$	931.3
Non-current	305.3		0.1		(5.1)		300.3
Government securities:
Current	547.1		0.1		(5.0)		542.2
Non-current	271.4		—		(3.3)		268.1
Mortgage and other asset backed securities:
Current	—		—		—		—
Non-current	139.1		0.1		(1.9)		137.3
Total marketable debt securities	$	2,199.1	$	0.3	$	(20.2)	$	2,179.2
Marketable equity securities
Marketable equity securities, non-current	$	1,133.8	$	—	$	(342.7)	$	791.1
Total marketable equity securities	$	1,133.8	$	—	$	(342.7)	$	791.1

Summary of contractual maturities: available-for-sale securities

The estimated fair value and amortized cost of our marketable debt securities classified as available-for-sale by contractual maturity are summarized as follows:

	As of March 31, 2023				As of December 31, 2022
(In millions)	Estimated Fair Value		Amortized Cost		Estimated Fair Value		Amortized Cost
Due in one year or less	$	2,143.1	$	2,151.5	$	1,473.5	$	1,483.3
Due after one year through five years	962.2		965.8		694.4		703.7
Due after five years	16.0		16.6		11.3		12.1
Total marketable debt securities	$	3,121.3	$	3,133.9	$	2,179.2	$	2,199.1

Proceeds from marketable debt securities

The proceeds from maturities and sales of marketable debt securities and resulting realized gains and losses are summarized as follows:

	For the Three Months Ended March 31,
(In millions)	2023		2022
Proceeds from maturities and sales	$	406.7	$	543.6
Realized gains	0.1		—
Realized losses	0.7		0.6