Cash, Cash Equivalents and Short-Term Investments - Schedule of Breakdown of the Short-Term Investments (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Less than 12 months
Fair Value	$ 0.8	$ 6.1
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	24.0	96.2
Gross Unrealized Losses	(0.2)	(1.0)
Total
Fair Value	24.8	102.3
Gross Unrealized Losses	(0.2)	(1.0)
Corporate notes and obligations
Less than 12 months
Fair Value	0.8	1.1
Gross Unrealized Losses	0.0	0.0
More than 12 months
Fair Value	24.0	58.5
Gross Unrealized Losses	(0.2)	(0.6)
Total
Fair Value	24.8	59.6
Gross Unrealized Losses	$ (0.2)	(0.6)
U.S. Treasury securities
Less than 12 months
Fair Value		5.0
Gross Unrealized Losses		0.0
More than 12 months
Fair Value		28.4
Gross Unrealized Losses		(0.2)
Total
Fair Value		33.4
Gross Unrealized Losses		(0.2)
Municipal securities
Less than 12 months
Fair Value		0.0
Gross Unrealized Losses		0.0
More than 12 months
Fair Value		4.5
Gross Unrealized Losses		(0.1)
Total
Fair Value		4.5
Gross Unrealized Losses		(0.1)
Asset backed securities
Less than 12 months
Fair Value		0.0
Gross Unrealized Losses		0.0
More than 12 months
Fair Value		4.8
Gross Unrealized Losses		(0.1)
Total
Fair Value		4.8
Gross Unrealized Losses		$ (0.1)

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

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