Cash, Cash Equivalents and Short-Term Investments - Schedule of Breakdown of the Short-Term Investments (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Less than 12 months
Fair Value	$ 12.5	$ 16.9
Gross Unrealized Losses	(0.1)	(0.2)
More than 12 months
Fair Value	187.8	213.9
Gross Unrealized Losses	(5.0)	(7.0)
Total
Fair Value	200.3	230.8
Gross Unrealized Losses	(5.1)	(7.2)
Corporate notes and obligations
Less than 12 months
Fair Value	1.3	1.9
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	88.3	103.8
Gross Unrealized Losses	(2.4)	(3.3)
Total
Fair Value	89.6	105.7
Gross Unrealized Losses	(2.4)	(3.3)
U.S. Treasury securities
Less than 12 months
Fair Value	5.1	9.0
Gross Unrealized Losses	0.0	(0.1)
More than 12 months
Fair Value	66.4	65.7
Gross Unrealized Losses	(1.8)	(2.5)
Total
Fair Value	71.5	74.7
Gross Unrealized Losses	(1.8)	(2.6)
Municipal securities
Less than 12 months
Fair Value	6.1	6.0
Gross Unrealized Losses	(0.1)	(0.1)
More than 12 months
Fair Value	17.9	23.1
Gross Unrealized Losses	(0.4)	(0.6)
Total
Fair Value	24.0	29.1
Gross Unrealized Losses	(0.5)	(0.7)
Asset backed securities
Less than 12 months
Fair Value	0.0	0.0
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	9.8	16.0
Gross Unrealized Losses	(0.2)	(0.3)
Total
Fair Value	9.8	16.0
Gross Unrealized Losses	(0.2)	(0.3)
U.S. agency obligations
Less than 12 months
Fair Value	0.0	0.0
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	3.7	3.6
Gross Unrealized Losses	(0.1)	(0.2)
Total
Fair Value	3.7	3.6
Gross Unrealized Losses	(0.1)	(0.2)
Supranational securities
Less than 12 months
Fair Value	0.0	0.0
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	1.7	1.7
Gross Unrealized Losses	(0.1)	(0.1)
Total
Fair Value	1.7	1.7
Gross Unrealized Losses	$ (0.1)	$ (0.1)

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions

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