Expiration date of warrants held.

No definition available.

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- Definition

Warrants issued to purchase common stock.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The number of exercisable share warrants that may be converted as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

It represents value of warrant liabilities.

+ References

No definition available.

+ Details

Name:	syn_WarrantLiabilities
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Warrants exercisable price per share.

+ References

No definition available.

+ Details

Name:	syn_WarrantsExercisablePricePerShare
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Period Type:	duration

- Definition

Number of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

+ Details

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

- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ 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)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section 25

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_WarrantMember
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Period Type:

Stock Purchase Warrants (Details Textual) (USD $)	3 Months Ended		1 Months Ended	0 Months Ended
Stock Purchase Warrants (Details Textual) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Oct. 25, 2012	Oct. 10, 2014	Dec. 31, 2014
Fair Value Adjustment of Warrants	$ 4,152,000us-gaap_FairValueAdjustmentOfWarrants	$ 0us-gaap_FairValueAdjustmentOfWarrants
Warrant liabilities	10,908,000syn_WarrantLiabilities				6,756,000syn_WarrantLiabilities
Class of Warrant or Right, Outstanding	316,522
Warrant [Member]
Issuance Of Warrants To Purchase Of Common Stock			635,855
Warrants Exercisable Price Per Share			$ 1.60
Investment Warrants Expiration Date1			Oct. 25, 2017
Stock Warrants [Member]
Proceeds from Issuance of Common Stock				19,100,000
Sale of Stock, Number of Shares Issued in Transaction				14,059,616
Sale of Stock, Price Per Share				$ 1.47
Issuance Of Warrants To Purchase Of Common Stock				0.5
Share Based Compensation Arrangement By Share Based Payment Award Warrants Exercisable Number				7,029,808
Warrants Exercisable Price Per Share				$ 1.75
Fair Value Adjustment of Warrants	10,900,000
Warrant liabilities	$ 4,200,000
Investment Warrants Expiration Date1				Oct. 10, 2019