Related Parties and Related Commitments and Contingencies - Schedule of Remaining Guarantee Obligations (Details) - Flash Ventures $ in Millions	Jun. 27, 2025 USD ($)
Guarantor Obligations [Line Items]
2026	$ 631
2027	365
2028	226
2029	103
2030	79
Total guarantee obligations	1,404
Payment of Principal Amortization
Guarantor Obligations [Line Items]
2026	507
2027	259
2028	124
2029	48
2030	16
Total guarantee obligations	954
Purchase Option Exercise Price at Final Lease Terms
Guarantor Obligations [Line Items]
2026	124
2027	106
2028	102
2029	55
2030	63
Total guarantee obligations	$ 450

Guarantee Obligations, Maximum Exposure, Year Five

No definition available.

Name:	sndk_GuaranteeObligationsMaximumExposureYearFive
Namespace Prefix:	sndk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions due within the fourth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	sndk_GuaranteeObligationsMaximumExposureYearFour
Namespace Prefix:	sndk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	sndk_GuaranteeObligationsMaximumExposureYearOne
Namespace Prefix:	sndk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions due within the third fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	sndk_GuaranteeObligationsMaximumExposureYearThree
Namespace Prefix:	sndk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions due within the second fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	sndk_GuaranteeObligationsMaximumExposureYearTwo
Namespace Prefix:	sndk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_EquityMethodInvesteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=sndk_PaymentOfPrincipalAmortizationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=sndk_PurchaseOptionExercisePriceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: