Income Taxes (Details Textual) $ in Millions	Sep. 30, 2023 USD ($)
Income Tax Contingency [Line Items]
Deferred tax assets, unrecognized tax benefit	$ 85.0
Decrease in unrecognized tax benefits is reasonably possible	460.0
ADUHELM
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 450.0

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-2

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