The amount of grants awarded from a governmental agency.

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- Definition

Represents the expenses incurred to secure and defend patents during the period.

+ References

No definition available.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Impairment

-URI http://asc.fasb.org/extlink&oid=6515133

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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Revenue earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

+ 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

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Name Accounting Standards Codification

-Topic 740

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-Section 50

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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Summary of Significant Accounting Policies (Details) (USD $)	1 Months Ended	12 Months Ended
	Mar. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Patents
Patent expenses		$ 1,900,000snta_PatentExpenses	$ 2,900,000snta_PatentExpenses	$ 1,800,000snta_PatentExpenses
Income Taxes
Uncertain tax items		0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Amount of accrued interest or penalties related to uncertain tax positions		0	0
Impairment of Long-Lived Assets
Impairment of assets		0	0
Grant Revenue
Amount of grant awarded	1,000,000snta_AmountOfGrantAwarded
Grant revenue		$ 0us-gaap_RevenueFromGrants	$ 0us-gaap_RevenueFromGrants	$ 147,000us-gaap_RevenueFromGrants
Minimum
Property and Equipment
Estimated useful lives		3 years
Maximum
Property and Equipment
Estimated useful lives		7 years