Represents the percentage of the term loan amounts relating to the issuance of warrants to purchase shares of the entity's common stock.

No definition available.

+ Details

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Namespace Prefix:	sien_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents to the term of the warrants, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	sien_TermOfWarrants
Namespace Prefix:	sien_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit 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)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ 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)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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

- Details

Name:	us-gaap_CounterpartyNameAxis=sien_OxfordFinanceLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=sien_TrancheBAndCTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=sien_TrancheDTermLoanMember
Namespace Prefix:
Data Type:	na
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Period Type:

Stockholders' Equity (Warrants) (Details) - $ / shares		1 Months Ended
Stockholders' Equity (Warrants) (Details) - $ / shares	Jan. 17, 2013	Jun. 30, 2014	Dec. 31, 2016
Common Stock Warrants
Aggregate number of common shares to purchase			47,710
Oxford Finance, LLC
Common Stock Warrants
Exercise price (in dollars per share)	$ 14.671	$ 14.671
Tranche A, B and C loans \| Oxford Finance, LLC
Common Stock Warrants
Warrant term	7 years
Percentage of term loan amounts	3.00%
Tranche D term loan \| Oxford Finance, LLC
Common Stock Warrants
Warrant term		7 years
Percentage of term loan amounts		2.50%