Income Taxes - Tax Rate (Details)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%	21.00%
State taxes	1.10%	0.80%	0.70%
Taxes on foreign earnings	(4.90%)	(10.50%)	(3.30%)
Tax credits	(1.70%)	(3.80%)	(1.20%)
Purchased intangible assets	0.30%	(1.60%)	0.70%
TECFIDERA impairment	0.00%	0.00%	1.80%
GILTI	0.70%	1.30%	1.30%
Sale of Samsung Bioepis	(1.60%)	0.00%	0.00%
Litigation settlement agreement	2.60%	0.00%	0.00%
Neurimmune tax impacts	2.30%	(5.30%)	(0.10%)
Internal reorganization	(1.40%)	0.00%	0.00%
Other	(0.80%)	1.10%	(1.20%)
Effective tax rate	17.60%	3.00%	19.70%

Effective Income Tax Rate Reconciliation, Intellectual Property Rights Reorganization

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Effective Income Tax Rate Reconciliation, Litigation Settlement, Percent

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Effective Tax Rate Reconciliation, GILTI tax

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to disposition of a business not qualifying as a discontinued operation.

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-SubTopic 10
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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