Stock Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Stock compensation
Stock compensation expense	$ 53.4	$ 43.8
Dividend yield (as a percent)	0.00%
Assumed annualized forfeiture rate (as a percent)	5.00%
Share-based Payment Arrangement, Option
Stock compensation
Stock option grant term	10 years
Vesting period	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 dollars)	$ 42.3
Vesting period of recognition of the unrecognized compensation cost of nonvested awards	1 year 1 month 6 days
Share-based Payment Arrangement, Option \| Share-based Payment Arrangement, Tranche One
Stock compensation
Vesting period	1 year
Share-based Payment Arrangement, Option \| Share-based Payment Arrangement, Tranche Two
Stock compensation
Vesting period	36 months
Restricted Stock Units (RSUs)
Stock compensation
Vesting period	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 dollars)	$ 202.8
Vesting period of recognition of the unrecognized compensation cost of nonvested awards	1 year 9 months 18 days
Performance Shares
Stock compensation
Stock compensation expense	$ 6.5	1.8
Unrecognized compensation cost for nonvested option (in dollars)	$ 24.1
Vesting period of recognition of the unrecognized compensation cost of nonvested awards	1 year 8 months 12 days
Performance Shares \| Minimum
Stock compensation
Vesting period	3 years
Performance Shares \| Maximum
Stock compensation
Vesting period	4 years
Research and Development Expense
Stock compensation
Stock compensation expense	$ 31.0	26.3
Selling, General and Administrative Expenses
Stock compensation
Stock compensation expense	21.6	16.9
Cost of Sales
Stock compensation
Stock compensation expense	$ 0.8	$ 0.6

Represents the expected annualized forfeiture rate for options granted.

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Represents the number of shares awarded for each restricted share units.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under 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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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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