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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period from grant to expiration date of share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Stock Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Stock compensation
Stock compensation expense	$ 67.3	$ 64.6	$ 131.4	$ 125.6
Dividend yield (as percent)			0.00%
Shares Subject to Outstanding Options
Stock compensation
Stock option grant term (in years)			10 years
Vesting period (in years)			4 years
Percentage of units vesting at the end of each calendar year (as a percent)			25.00%
Unrecognized compensation cost for nonvested option (in USD per share)	20.8		$ 20.8
Vesting period of recognition of the unrecognized compensation cost of nonvested awards (in years)			1 year 1 month 6 days
Shares Subject to Outstanding Options \| Share-based Payment Arrangement, Tranche One
Stock compensation
Vesting period (in years)			1 year
Shares Subject to Outstanding Options \| Share-based Payment Arrangement, Tranche Two
Stock compensation
Vesting period (in years)			36 months
Restricted Stock Units (RSUs)
Stock compensation
Vesting period (in years)			4 years
Percentage of units vesting at the end of each calendar year (as a percent)			25.00%
Number of shares awarded for each RSU (in shares)			1
Unrecognized compensation cost for nonvested option (in USD per share)	177.1		$ 177.1
Vesting period of recognition of the unrecognized compensation cost of nonvested awards (in years)			1 year 2 months 12 days
Performance Shares
Stock compensation
Stock compensation expense	8.4	6.9	$ 15.4	10.0
Unrecognized compensation cost for nonvested option (in USD per share)	28.0		$ 28.0
Vesting period of recognition of the unrecognized compensation cost of nonvested awards (in years)			1 year 10 months 24 days
Performance Shares \| Minimum
Stock compensation
Vesting period (in years)			3 years
Performance Shares \| Maximum
Stock compensation
Vesting period (in years)			6 years
Income Statement Location [Axis]: us-gaap:CostOfRevenue
Stock compensation
Stock compensation expense	0.9	0.8	$ 1.8	1.7
Income Statement Location [Axis]: us-gaap:ResearchAndDevelopmentExpense
Stock compensation
Stock compensation expense	38.2	37.7	77.4	74.4
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Stock compensation
Stock compensation expense	$ 28.2	$ 26.1	$ 52.2	$ 49.5
Stock Incentive Plan 2010
Stock compensation
Shares reserved for future issuance (in shares)	74,953,475		74,953,475
2024 Inducement Plan
Stock compensation
Shares reserved for future issuance (in shares)	2,000,000		2,000,000