Property, Plant and Equipment - Summary of Acquisitions and Capitalized Interest by Operating Segment (Details) € in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2024 EUR (€) segment	Dec. 31, 2023 EUR (€)
Disclosure of detailed information about property, plant and equipment [line items]
Additions other than through business combinations, property, plant and equipment	€ 591	€ 1,693
Interest costs capitalised	€ 22	26
Number of operating segments \| segment	2
Dupixent
Disclosure of detailed information about property, plant and equipment [line items]
Additions other than through business combinations, property, plant and equipment	€ 535	1,592
Dupixent \| Manufacturing & Supply
Disclosure of detailed information about property, plant and equipment [line items]
Additions other than through business combinations, property, plant and equipment	366	1,188
Opella \| Manufacturing & Supply
Disclosure of detailed information about property, plant and equipment [line items]
Additions other than through business combinations, property, plant and equipment	41	90
Opella
Disclosure of detailed information about property, plant and equipment [line items]
Additions other than through business combinations, property, plant and equipment	€ 56	€ 101

The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2023-01-01
-Paragraph 73
-Subparagraph e
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2023-en-r&anchor=para_73_e_i&doctype=Standard
-URIDate 2023-03-23

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Balance Type:	debit
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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The amount of interest costs that an entity incurs in connection with the borrowing of funds that are directly attributable to the acquisition, construction or production of a qualifying asset and which form part of the cost of that asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2023-03-23

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- Definition

Number of operating segments.

+ References

No definition available.

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- Details

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- Details

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- Details

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