Adjustments to Additional Paid in Capital, Imputed Interest Expense, Related Party

No definition available.

Name:	smmt_AdjustmentsToAdditionalPaidInCapitalImputedInterestExpenseRelatedParty
Namespace Prefix:	smmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Notes Payable, Related Parties, Maturity Triggering Event, Public Offering Proceeds Threshold

+ References

No definition available.

+ Details

Name:	smmt_NotesPayableRelatedPartiesMaturityTriggeringEventPublicOfferingProceedsThreshold
Namespace Prefix:	smmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Notes Payable, Related Parties, Maximum Term

+ References

No definition available.

+ Details

Name:	smmt_NotesPayableRelatedPartiesMaximumTerm
Namespace Prefix:	smmt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Payment Of Accrued Interest To Related Parties

+ References

No definition available.

+ Details

Name:	smmt_PaymentOfAccruedInterestToRelatedParties
Namespace Prefix:	smmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

+ Details

Name:	us-gaap_InterestExpenseRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromRelatedPartyDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

No definition available.

+ Details

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

- Definition

The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfRelatedPartyDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AdditionalPaidInCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=smmt_RightsOfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=smmt_A2022NoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=smmt_InitialPurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Promissory Note Payable to a Related Party (Details) - USD ($) $ in Thousands						1 Months Ended	3 Months Ended		9 Months Ended
	Aug. 10, 2022	Aug. 08, 2022	Mar. 10, 2022	May 12, 2021	Mar. 24, 2021	Aug. 08, 2022	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Related Party Transaction [Line Items]
Proceeds from related party promissory notes									$ 25,000	$ 110,000
Repayment of related party promissory notes									25,000	110,000
Proceeds from offering									100,000	75,000
Imputed interest							$ 570		1,063	103
Additional Paid-In Capital
Related Party Transaction [Line Items]
Imputed interest							570		1,063	103
Rights offering
Related Party Transaction [Line Items]
Proceeds from offering		$ 100,000		$ 75,000		$ 100,000
Chief Executive Officer
Related Party Transaction [Line Items]
Interest expense							0	$ 692	244	1,497
Chief Executive Officer \| Additional Paid-In Capital
Related Party Transaction [Line Items]
Imputed interest							$ 570	$ 0	$ 1,063	$ 159
Chief Executive Officer \| 2022 Note
Related Party Transaction [Line Items]
Proceeds from related party promissory notes			$ 25,000
Promissory note			25,000
Notes payable, maturity triggering event, public offering proceeds threshold			$ 25,000
Notes payable, maximum term			18 months
Repayment of related party promissory notes	$ 25,000
Payment of related party accrued interest	$ 434
Chief Executive Officer \| Initial Note
Related Party Transaction [Line Items]
Proceeds from related party promissory notes					$ 55,000
Promissory note					55,000
Notes payable, maturity triggering event, public offering proceeds threshold					$ 55,000
Notes payable, maximum term					13 months