Annual base rent increase percentage for operating lease.

No definition available.

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Namespace Prefix:	stok_
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Period Type:	duration

- Definition

Area of space subject to operating lease.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of space subject to sublease.

+ References

No definition available.

+ Details

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Namespace Prefix:	stok_
Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Commitments and contingencies.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of renewal option to extend operating lease terms.

+ References

No definition available.

+ Details

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Namespace Prefix:	stok_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating lease commencement date.

+ References

No definition available.

+ Details

Name:	stok_OperatingLeaseCommencementDate
Namespace Prefix:	stok_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating lease cost per year.

+ References

No definition available.

+ Details

Name:	stok_OperatingLeaseCostPerYear
Namespace Prefix:	stok_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Payment for license and collaboration agreement.

+ References

No definition available.

+ Details

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

- Definition

Percentage of sublease annual rent increases.

+ References

No definition available.

+ Details

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Namespace Prefix:	stok_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date which lease or group of leases is set to expire, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

+ Details

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

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-4

+ Details

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

- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479365/842-20-25-6

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

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

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-7

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Details) $ in Thousands		1 Months Ended					3 Months Ended		6 Months Ended
	Jan. 21, 2026 USD ($) ft² Option	Sep. 30, 2025 USD ($) ft²	Jan. 31, 2025 USD ($) ft² Option	Dec. 31, 2023 USD ($) ft²	Sep. 30, 2021 ft²	Aug. 31, 2018 USD ($) ft²	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Jul. 31, 2025 USD ($)	Apr. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Commitments And Contingencies [Line Items]
Area of space subject to operating lease \| ft²	98,500		7,581			23,000
Operating lease term			3 years 3 months			3 years
Operating lease cost per year			$ 700			$ 900
Annual base rent increase percentage for operating lease			2.00%			3.00%
Operating lease commencement date			Jul. 08, 2025			Dec. 10, 2018
Operating lease expiration date	Mar. 31, 2038
Operating right-of-use assets							$ 1,870		$ 1,870		$ 3,101	$ 1,800
Operating lease liabilities							2,682		2,682			$ 1,800
Number of options to renewal operating lease term \| Option	2		2
Operating lease, renewal term	5 years		3 years
Sublease terms commence		$ 400
Area of space subject to sublease \| ft²		7,581
Percentage of sublease annual rent increases		2.00%
Impairment of right of use asset		$ 700
Operating lease, option to extend	The Lease Agreement will expire on March 31, 2038, and includes two options to further extend the Lease Agreement for an additional five years at the then-prevailing market rate.
Operating lease, existence of option to extend [true false]	true
Operating leases expense	$ 86,600
Letter of Credit
Commitments And Contingencies [Line Items]
Security Deposit	$ 3,000
Southampton Agreement
Commitments And Contingencies [Line Items]
Payment for license and collaboration agreement									8,900
ASU 2016-02
Commitments And Contingencies [Line Items]
Operating leases expense							$ 600	$ 700	$ 1,200	$ 1,400
Lease Commencement on December 15, 2021
Commitments And Contingencies [Line Items]
Area of space subject to operating lease \| ft²					23,000
Operating lease term					3 years
Operating lease commencement date					Dec. 15, 2021
Operating lease expiration date					Dec. 31, 2024
Operating right-of-use assets														$ 3,500
Operating lease liabilities														$ 3,500
Lease Commencement on April 2022
Commitments And Contingencies [Line Items]
Area of space subject to operating lease \| ft²					15,000
Operating lease commencement date					Apr. 01, 2022
Operating lease expiration date					Dec. 31, 2024
Operating right-of-use assets													$ 1,800
Operating lease liabilities													$ 1,800
Lease Commencement on January 1, 2025
Commitments And Contingencies [Line Items]
Area of space subject to operating lease \| ft²				38,000
Operating lease term				2 years
Operating lease commencement date				Jan. 01, 2025
Operating lease expiration date				Dec. 31, 2026
Operating right-of-use assets				$ 4,100
Operating lease liabilities				$ 4,100