Business acquisition, number of free shares held by the holders.

No definition available.

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Period Type:	instant

- Definition

Business Acquisition, Number Of Free Shares Outstanding Subject To Purchase

+ References

No definition available.

+ Details

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Namespace Prefix:	sgmo_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Business acquisition, number of shares acquired.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgmo_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the purchase of noncontrolling interest during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

+ Details

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Balance Type:	credit
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

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- Details

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- Details

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FAIR VALUE MEASUREMENTS - Narrative (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		32 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Jul. 20, 2018
Debt Securities, Available-for-sale [Line Items]
Purchase of additional Sangamo France shares	$ 65	$ 0
Sangamo France \| Share purchase agreement and tender offer agreement
Debt Securities, Available-for-sale [Line Items]
Number of free shares held by the holders (in shares)				477
Number of shares acquired (in shares)			453
Purchase of additional Sangamo France shares	$ 1,100
Number of free shares outstanding subject to purchase (in shares)	24