Amount expected to be recognized in earnings for the specified restructuring cost.

Name:	us-gaap_RestructuringAndRelatedCostExpectedCost1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of expected cost remaining for the specified restructuring cost.

+ References

No definition available.

+ Details

Name:	us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

+ Details

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

- Definition

The number of positions eliminated during the period as a result of restructuring activities.

+ References

No definition available.

+ Details

Name:	us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

+ References

No definition available.

+ Details

Name:	us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedPeriodPercent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

+ Details

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

- Details

Name:	us-gaap_RestructuringPlanAxis=sgmo_NovemberRestructuringPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_ResearchAndDevelopmentExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringPlanAxis=sgmo_FranceRestructuringPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringPlanAxis=sgmo_April2023RestructuringPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringPlanAxis=sgmo_November2023RestructuringPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_TitleOfIndividualAxis=sgmo_FullTimeEmployeesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_TitleOfIndividualAxis=sgmo_ContractedEmployeesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

RESTRUCTURING CHARGES - Narrative (Details) $ in Millions				12 Months Ended
RESTRUCTURING CHARGES - Narrative (Details) $ in Millions	Mar. 01, 2024 employee	Nov. 01, 2023 employee	Apr. 26, 2023 employee	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
November Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net				$ 0.2	$ 6.7
November Restructuring Plan \| Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					5.0
November Restructuring Plan \| General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					1.7
France Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Number of employees eliminated in restructuring \| employee	93
Percentage of positions eliminated in restructuring	24.00%
Restructuring expected cost					4.8
Restructuring charges, net				0.1	4.7
France Restructuring Plan \| Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					3.6
France Restructuring Plan \| General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					1.1
April 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Number of employees eliminated in restructuring \| employee			110
Percentage of positions eliminated in restructuring			23.00%
Restructuring charges, net				0.0	5.0
April 2023 Restructuring Plan \| Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					3.8
April 2023 Restructuring Plan \| General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net					1.2
November 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Number of employees eliminated in restructuring \| employee		162
Percentage of positions eliminated in restructuring		40.00%
November 2023 Restructuring Plan \| Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost					7.8
Additional estimated costs remaining				0.9
November 2023 Restructuring Plan \| Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost					$ 8.8
Additional estimated costs remaining				$ 1.9
November 2023 Restructuring Plan \| Full-Time Employees
Restructuring Cost and Reserve [Line Items]
Number of employees eliminated in restructuring \| employee		108
November 2023 Restructuring Plan \| Contracted Employees
Restructuring Cost and Reserve [Line Items]
Number of employees eliminated in restructuring \| employee		54