Stock Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock compensation
Stock compensation expense	$ 46.5	$ 44.8	$ 90.3	$ 92.1
Assumed annualized forfeiture rate (as a percent)			5.00%
Weighted-average fair value assumptions
Valuation method			Black-Scholes valuation model
Dividend yield (as a percent)			0.00%
Research and Development Expense [Member]
Stock compensation
Stock compensation expense	28.1	28.0	$ 54.4	57.9
Selling, General and Administrative Expenses [Member]
Stock compensation
Stock compensation expense	17.7	16.4	34.6	33.6
Cost of product revenues
Stock compensation
Stock compensation expense	$ 0.7	$ 0.4	$ 1.3	$ 0.6
Employee Stock Purchase Plan
Weighted-average fair value assumptions
Average risk-free interest rates (as a percent)	2.92%	0.25%	2.77%	0.18%
Average expected life (in years)	6 months	6 months	6 months	6 months
Volatility (as a percent)	39.00%	26.00%	28.00%	33.00%
Weighted-average fair value (in dollars per share)	$ 14.91	$ 16.14	$ 14.53	$ 18.48
Employee Stock Option
Weighted-average fair value assumptions
Average risk-free interest rates (as a percent)	3.04%	0.75%	1.67%	0.44%
Average expected life (in years)	5 years 6 months 3 days	5 years 3 months 25 days	4 years 9 months 7 days	4 years 10 months 2 days
Volatility (as a percent)	33.00%	38.00%	37.00%	39.00%
Weighted-average fair value (in dollars per share)	$ 26.35	$ 29.55	$ 25.30	$ 29.80
Unrecognized compensation
Unrecognized compensation cost for nonvested option (in dollars)	$ 53.0		$ 53.0
Vesting period of recognition of the unrecognized compensation cost of nonvested awards			1 year
Restricted Stock Units (RSUs)
Unrecognized compensation
Unrecognized compensation cost for nonvested option (in dollars)	128.8		$ 128.8
Vesting period of recognition of the unrecognized compensation cost of nonvested awards			1 year 7 months 6 days
Performance Stock Units (PSUs)
Stock compensation
Stock compensation expense	0.1	$ 0.6	$ 1.9	$ 3.2
Unrecognized compensation
Unrecognized compensation cost for nonvested option (in dollars)	$ 22.7		$ 22.7
Vesting period of recognition of the unrecognized compensation cost of nonvested awards			1 year 10 months 24 days

Represents the expected annualized forfeiture rate for options granted.

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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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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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Description of method used to estimate fair value of award under share-based payment arrangement.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Expected term of 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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