Name:	ifrs-full_DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesLineItems
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The increase (decrease) in liabilities arising from financing activities. [Refer: Liabilities arising from financing activities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 44B
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_44B&doctype=Standard
-URIDate 2025-03-27

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The increase (decrease) in liabilities arising from financing activities resulting from changes in fair values. [Refer: Liabilities arising from financing activities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
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-Subparagraph d
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-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 166
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_d&doctype=Standard
-URIDate 2025-03-27

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-Note Effective 2027-01-01
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The increase (decrease) in liabilities arising from financing activities resulting from the effect of changes in foreign exchange rates. [Refer: Liabilities arising from financing activities]

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-Name IAS
-Number 7
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-Paragraph 44B
-Subparagraph c
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-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
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-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_c&doctype=Standard
-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 166
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_c&doctype=Standard
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The increase (decrease) in liabilities arising from financing activities resulting from financing cash flows. [Refer: Cash flows from (used in) financing activities; Liabilities arising from financing activities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
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-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
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-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_a&doctype=Standard
-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
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-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166_a&doctype=Standard
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The increase in liabilities arising from financing activities resulting from new leases. [Refer: Liabilities arising from financing activities]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Section A Statement of cash flows for an entity other than a financial institution
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&doctype=Illustrative%20Examples&dita_xref=IAS07_IE_A_TI
-URIDate 2025-03-27

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-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 44B
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_44B&doctype=Standard
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The amount of liabilities for which cash flows were, or future cash flows will be, classified in the statement of cash flows as cash flows from financing activities. [Refer: Cash flows from (used in) financing activities; Liabilities]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 44D
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_44D&doctype=Standard
-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 166
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166&doctype=Standard
-URIDate 2025-03-27

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-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 166
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_166&doctype=Standard
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Name:	ifrs-full_LiabilitiesArisingFromFinancingActivities
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Balance Type:	credit
Period Type:	instant

The cash inflow from borrowings obtained. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_17_c&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The increase (decrease) in liabilities arising from financing activities resulting from accrued interest payable.

No definition available.

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

The increase (decrease) in liabilities arising from financing activities resulting from forgiveness.

No definition available.

Name:	shmd_IncreaseDecreaseThroughForgivenessLiabilitiesArisingFromFinancingActivities
Namespace Prefix:	shmd_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The cash outflow for interest paid, classified as financing activities.

No definition available.

Name:	shmd_IncreaseDecreaseThroughInterestPaid
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for payment of lease liabilities, classified as financing activities. [Refer: Lease liabilities]

No definition available.

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

The cash inflow from changes in ownership interests in subsidiaries that do not result in a loss of control. [Refer: Total for all subsidiaries [member]]

No definition available.

Name:	shmd_ProceedsFromChangesInOwnershipInterestInSubsidiaries
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Period Type:	duration

The cash outflow to settle borrowings, Repayments of Loans Including Adjustments.

No definition available.

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

Amount of cash outflow (inflow) from transaction with minority shareholder classified as financing activities.

No definition available.