Sale Of Stock, Number Of Shares Issued In Transaction, Including Shares In Secondary Offering

No definition available.

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

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedOnTransaction
Namespace Prefix:	us-gaap_
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

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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

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

- 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

Name:	us-gaap_SubsidiarySaleOfStockAxis=sibn_FollowOnPublicOfferingMember
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- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=sibn_FollowOnPublicOfferingAndSecondaryOfferingMember
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- Details

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- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=sibn_SecondaryOfferingMember
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The Company and Nature of Business (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			3 Months Ended
	Feb. 29, 2020	Jan. 31, 2020	Oct. 31, 2018	Mar. 31, 2020
IPO
Subsidiary, Sale of Stock [Line Items]
Number of shares issued (in shares)			8,280,000
Public offering price (in dollars per share)			$ 15.00
Net proceeds from sale of stock			$ 113.4
Follow-on public offering
Subsidiary, Sale of Stock [Line Items]
Number of shares issued (in shares)		2,490,053
Public offering price (in dollars per share)		$ 21.50
Net proceeds from sale of stock		$ 50.3
Public offering costs				$ 0.4
Follow-on public offering and secondary offering
Subsidiary, Sale of Stock [Line Items]
Number of shares in transaction, including shares in secondary offering		4,300,000
Underwriters option
Subsidiary, Sale of Stock [Line Items]
Number of shares issued (in shares)	645,000
Public offering price (in dollars per share)	$ 21.50
Net proceeds from sale of stock	$ 13.0
Secondary offering by selling shareholders
Subsidiary, Sale of Stock [Line Items]
Public offering costs				$ 0.2