Portion of future lease payments accrued as part of 2013 Restructuring Plan.

No definition available.

Name:	smsi_AccruedLeaseExpenses
Namespace Prefix:	smsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Extension of time for performance under the grant terms.

+ References

No definition available.

+ Details

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Namespace Prefix:	smsi_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of lease incentives per square foot received from landlord for the improvement of space.

+ References

No definition available.

+ Details

Name:	smsi_IncentivesPricePerSquareFoot
Namespace Prefix:	smsi_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount provided by lessor for the improvement of space.

+ References

No definition available.

+ Details

Name:	smsi_LeaseIncentiveAmountForImprovementOfSpace
Namespace Prefix:	smsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Minimum number of people agreed to employ in exchange for start up grant.

+ References

No definition available.

+ Details

Name:	smsi_MinimumNumberOfPeopleToBeEmployed
Namespace Prefix:	smsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Estimated income to be received from sublease of office space.

+ References

No definition available.

+ Details

Name:	smsi_OperatingLeasesExpectedFutureSubleaseIncome
Namespace Prefix:	smsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of time in which to employ minimum number of people under initial terms of the grant.

+ References

No definition available.

+ Details

Name:	smsi_PeriodInWhichPeopleToBeEmployed
Namespace Prefix:	smsi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount received from State of Pennsylvania to help fund the start up of new facility.

+ References

No definition available.

+ Details

Name:	smsi_ProceedsFromGovernmentGrantForStartUpNewFacility
Namespace Prefix:	smsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A general description of the nature of the existing leasing arrangements of a lessee for all operating leases including, but not limited to: (1) rental escalation clauses; (2) renewal or purchase options; (3) guarantees or indemnities, if any, (4) restrictions imposed by lease arrangements; (5) unusual provisions or conditions; (6) contingent rentals, if any; and (7) lease expiration dates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6452660&loc=d3e36991-112694

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 1)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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- Details

Name:	us-gaap_LeasesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

+ Details

Name:	us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013 People	Dec. 31, 2012	Sep. 26, 2011
Leases [Abstract]
Expiration of non-cancellable operating leases	Through 2022
Accrued lease commitments expense	$ 5.6smsi_AccruedLeaseExpenses
Estimated sublease income	3.0
Rent expense under operating leases	1.2us-gaap_OperatingLeasesRentExpenseNet	2.4us-gaap_OperatingLeasesRentExpenseNet	2.7us-gaap_OperatingLeasesRentExpenseNet
Incentives per square feet	40.00smsi_IncentivesPricePerSquareFoot
Incentives for improvements to space	2.2
Amount received to start-up new facility				$ 1.0
Minimum number of people to be employed		232smsi_MinimumNumberOfPeopleToBeEmployed
Time period to meet employment commitment		3 years
New deadline to meet employment commitment	Feb. 28, 2015