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- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 53
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_53_e&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 115
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_115_e&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 115
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_115_e&doctype=Standard
-URIDate 2025-03-27

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Data Type:	xbrli:monetaryItemType
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The amount of operating lease income. Operating lease is a lease that does not transfer substantially all the risks and rewards incidental to ownership of an underlying asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 90
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_90_b&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 125
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_125&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 125
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_125&doctype=Standard
-URIDate 2025-03-27

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The amount of undiscounted operating lease payments to be received. Operating lease is a lease that does not transfer substantially all the risks and rewards incidental to ownership of an underlying asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph 97
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_97&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 124
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_124&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 124
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_124&doctype=Standard
-URIDate 2025-03-27

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Balance Type:	debit
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The weighted average lessee's incremental borrowing rate applied to lease liabilities recognised in the statement of financial position at the date of initial application of IFRS 16. The incremental borrowing rate is the rate of interest that a lessee would have to pay to borrow over a similar term, and with a similar security, the funds necessary to obtain an asset of a similar value to the right-of-use asset in a similar economic environment.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2025-01-01
-Paragraph C12
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2025-en-r&anchor=para_C12_a&doctype=Appendix&subtype=C
-URIDate 2025-03-27

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Amount of sublease income per month.

No definition available.

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Namespace Prefix:	shmd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The interest rate used to discount the lease payments in the sale and leaseback transaction.

No definition available.

Name:	shmd_SaleAndLeasebackTransactionInterestRate
Namespace Prefix:	shmd_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Lease term for sale and leaseback transaction, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	shmd_SaleLeasebackTransactionLesseeLeaseTerm
Namespace Prefix:	shmd_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The net book value of the asset(s) sold in connection with the sale of the property to another party and lease back to the seller.

No definition available.

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Namespace Prefix:	shmd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Renewal lease term for sale and leaseback transaction, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	shmd_SaleLeasebackTransactionLesseeRenewalLeaseTerm
Namespace Prefix:	shmd_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The amount of undiscounted lease payments to be made.

No definition available.