v3.24.3
Investments (Tables)
 9 Months Ended
Sep. 30, 2024
Investments, Debt and Equity Securities [Abstract]  
Schedule of Marketable Securities
The following table presents the remaining maturities and values of our marketable securities as of the dates shown.
 September 30, 2024December 31, 2023
(in millions, except maturities in months)Remaining
Maturities		Amortized CostFair ValueAmortized CostFair Value
U.S. treasury and government agencies3 to 77 months$23.0 $21.5 $24.9 $22.9 
Corporate debt securities8 to 103 months17.3 17.0 20.0 19.2 
State and municipal bonds6 to 169 months14.2 14.1 15.5 15.1 
Total marketable securities$54.5 $52.6 $60.4 $57.2 
Equity Investments without Readily Determinable Fair Values
The following table summarizes the activity related to these equity investments during the periods presented.
Three Months Ended
September 30,		Nine Months Ended
September 30,
(in millions)2024202320242023
Investment in equity securities$0.2 $10.3 $0.2 $15.3 
Upward adjustments (1)
— 2.3 — 20.0 
(1)     Our updated investment value in 2023 was determined using a hybrid backsolve method, a valuation approach incorporating both IPO and M&A scenarios to estimate the value based on recently issued shares.