Aggregate additional revenue recognition milestone method revenue achieved.

No definition available.

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- Definition

Aggregate additional revenue recognition milestone method revenue eligible to receive.

+ References

No definition available.

+ Details

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- Definition

Aggregate additional revenue recognition milestone method revenue to be recognized on acceptance of application.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of gene targets.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Collaboration and license agreements number of products approved under agreement.

+ References

No definition available.

+ Details

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

- Definition

Initial research term of agreement.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Milestone payments received.

+ References

No definition available.

+ Details

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

- Definition

Milestone revenue receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgmo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of additional gene targets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Number of gene targets.

+ References

No definition available.

+ Details

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

- Definition

Number of initial gene targets.

+ References

No definition available.

+ Details

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

- Definition

Number of research program.

+ References

No definition available.

+ Details

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

- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

+ Details

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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 730

-SubTopic 20

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 730

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 730

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of consideration recognized during the period for the milestone or milestones.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 28

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=19771982&loc=SL6892177-166501

+ Details

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- Definition

Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Details

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Major Customers, Partnerships and Strategic Alliances - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		1 Months Ended		12 Months Ended
	Jan. 31, 2014 Program	Mar. 31, 2015	Mar. 31, 2014	Jun. 30, 2012 Targets	Jan. 31, 2012 Targets	Dec. 31, 2014
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of research programs	2sgmo_NumberOfResearchProgram
Research and development		$ 14,980,000us-gaap_ResearchAndDevelopmentExpense	$ 12,083,000us-gaap_ResearchAndDevelopmentExpense
Biogen Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenues under agreement	20,000,000
Potential amount eligible to receive for certain milestones	126,300,000
Potential amount to be funded for achievement of specified commercialized and sales milestones	167,500,000
Milestone revenue receivable	293,800,000
Milestone payments received		0
Number of products approved		0
Royalty revenues		0
Research program to develop laboratory research reagents		40 months
Deferred revenue		14,100,000
Biogen Inc [Member] \| Beta-thalassemia [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone revenue receivable	7,500,000
Research and development		1,400,000	1,300,000
Biogen Inc [Member] \| Sickle cell disease [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone revenue receivable	7,500,000
Biogen Inc [Member] \| Other Projects [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development		1,100,000	0
Shire AG [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenues under agreement					13,000,000
Potential amount to be funded for achievement of specified commercialized and sales milestones					180,000,000
Number of products approved		0
Royalty revenues		0
Research program to develop laboratory research reagents		6 years
Deferred revenue		6,800,000
Research and development		4,500,000	4,800,000
Aggregate number of gene targets					7
Number of initial gene targets					4
Number of gene targets				5
Number of additional gene targets				2
IND or CTA submission amount					8,500,000
Milestone payment						1,000,000
Shire AG [Member] \| Maximum [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone revenue receivable					$ 33,500,000