The amount of contractual undiscounted cash flows in relation to lease liabilities before deducting finance charges. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 58
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_58&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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Balance Type:	credit
Period Type:	instant

- 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 2025-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2025-03-27

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items disclosing information related to the maturity analysis of lease payments.

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation and foreign currency effects for lease payments .

+ References

No definition available.

+ Details

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Namespace Prefix:	shmd_
Data Type:	xbrli:monetaryItemType
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LEASES - Maturity analysis (Details) - EUR (€) € in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disclosure of Maturity Analysis of Lease Payments [Line Items]
Gross lease liabilities - minimum lease payments	€ 10,688	€ 12,361
Discount and foreign currency effects	2,138	2,667
Present value of the lease liabilities	8,550	9,694	€ 10,886
Not later than 1 year
Disclosure of Maturity Analysis of Lease Payments [Line Items]
Gross lease liabilities - minimum lease payments	1,902	2,029
Later than 1 year and not later than 2 years
Disclosure of Maturity Analysis of Lease Payments [Line Items]
Gross lease liabilities - minimum lease payments	1,452	1,755
Later than 2 year and not later than five years
Disclosure of Maturity Analysis of Lease Payments [Line Items]
Gross lease liabilities - minimum lease payments	3,733	3,778
Later than 5 years
Disclosure of Maturity Analysis of Lease Payments [Line Items]
Gross lease liabilities - minimum lease payments	€ 3,600	€ 4,800