Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Mar. 31, 2022
Deferred tax assets:
Tax credits	$ 294.0	$ 252.8
Inventory, other reserves and accruals	219.2	203.7
Intangibles, net	989.6	1,153.9
IRC Section 174 capitalized research and development	733.9	570.8
Net operating loss	1,357.2	1,700.4
Share-based compensation	34.4	36.1
Other	318.4	293.3
Valuation allowance	(1,013.7)	(1,278.7)	$ (85.0)
Total deferred tax assets	2,933.0	2,932.3
Deferred tax liabilities:
Purchased inventory valuation step-up and intangible assets	(1,529.6)	(1,257.4)
Samsung Bioepis investment installments	0.0	(35.5)
GILTI	(1,054.8)	(1,136.9)
Depreciation, amortization and other	(214.9)	(215.7)
Total deferred tax liabilities	$ (2,799.3)	$ (2,645.5)

Deferred tax liabilities depreciation amortization other.

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Deferred Tax Liabilities, GILTI Tax Calculation

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
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-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from in-process research and development cost acquired in business combination or from joint venture formation or both.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from investments in unconsolidated subsidiaries and investments in other affiliates which are not controlled nor consolidated.

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