Consolidated Statement of Stockholders' Equity (Parenthetical) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Series B Preferred Stock [Member]
Shares issued in Series B preferred stock offering, issuance costs	$ 287

Shares issued in preferred stock offering issuance costs.

No definition available.

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