Financial Instruments

12 Months Ended

Dec. 31, 2023

Cash, Cash Equivalents And Marketable Securities [Abstract]

Cash, Cash Equivalents, and Marketable Securities [Text Block]

Financial Instruments

Cash, Cash Equivalents, and Marketable Securities

The following table summarizes the Company’s cash, cash equivalents, and marketable securities and the fair value categorization of the financial instruments measured at fair value on a recurring basis:


	As of December 31,
	2023		2022
	(In millions)
Cash	$	25.6	$	27.0
Time deposits	1.0		4.1
Money market funds (Level 1)	160.3		178.6
Debt securities issued by the U.S. Treasury (Level 1)	744.9		776.1
Total	$	931.8	$	985.8

Cash and cash equivalents	$	240.1	$	373.6
Restricted cash (included in Other long-term assets)	5.4		5.4
Total Cash, cash equivalents, and restricted cash	245.5		379.0
Marketable securities	686.3		606.8
Total	$	931.8	$	985.8

The gross and net unrealized gains and losses included in the fair value of the debt securities were not significant for the periods presented. All of the debt securities held as of December 31, 2023 are scheduled to mature in less than one year.

Fair Value Measurements

The fair value of the Company’s investments in money market funds approximates their face value. Such instruments are included in Cash and cash equivalents. The fair value of the debt securities consisting of U.S. Treasury bills is based on their quoted market prices. Debt securities purchased with original maturities in excess of three months are included in Marketable securities. The fair value of all of these financial instruments are classified as Level 1 in the fair value hierarchy.

As of December 31, 2023, the Company’s other financial instruments include cash, accounts receivable, restricted cash, and accounts payable whose carrying values approximated their fair values. The aggregate fair value of the Company’s senior notes is $1.69 billion and $1.65 billion as of December 31, 2023 and December 31, 2022, respectively. The fair values of these debt instruments are based on available market information from public data sources and are classified as Level 2.