Related party transactions - Lease Agreements - Summary (Details) - EUR (€) € in Thousands	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Leases balances
Right-of-use asset	€ 3,133,305		€ 3,612,456
Lease Agreements
Lease Transactions
Depreciation	19,124	€ 18,754
Interest expense	1,392	1,697
Lease expense	108	70
Leases balances
Right-of-use asset	93,174		110,041
Lease liability	96,465		112,863
Fresenius SE \| Lease Agreements
Lease Transactions
Depreciation	5,159	4,943
Interest expense	182	237
Lease expense	108	70
Leases balances
Right-of-use asset	19,451		22,997
Lease liability	20,010		24,953
Fresenius SE affiliates \| Lease Agreements
Lease Transactions
Depreciation	13,965	13,811
Interest expense	1,210	€ 1,460
Leases balances
Right-of-use asset	73,723		87,044
Lease liability	€ 76,455		€ 87,910

n/a

No definition available.

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- Definition

Expense relating to short-term leases and variable lease payments not included in measurement of lease liabilities

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The amount of depreciation of right-of-use assets. [Refer: Depreciation and amortisation expense; Right-of-use assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 53
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_a&doctype=Standard
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- Definition

The amount of interest expense on lease liabilities. [Refer: Lease liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 53
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_b&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 47
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Definition

The amount of assets that represent a lessee's right to use an underlying asset for the lease term that do not meet the definition of investment property. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 16
-IssueDate 2024-01-01
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-URIDate 2024-03-27

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