Stock-Based Compensation - Narrative (Details)	6 Months Ended
Jul. 28, 2013
Stock options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Performance shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance condition, highest potential performance level	200.00%
The maximum number of shares issued for performance unit awards	412,500
Remaining number of shares which would be settled in cash	402,500
Target performance metrics for performance unit awards, fiscal year 2014	100.00%
Target performance metrics for performance unit awards, fiscal year 2013	80.00%
Target performance metrics for performance unit awards, fiscal year 2012	97.00%
Employee stock unit awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Non-employee director stock unit awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Vested but unsettled stock units	161,182

Vesting period of stock unit awards granted to non-employee directors.

No definition available.

Name:	smtc_NonEmployeeDirectorsShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod
Namespace Prefix:	smtc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Remaining Number Of Shares Which Would Be Settled In Cash

+ References

No definition available.

+ Details

Name:	smtc_RemainingNumberOfSharesWhichWouldBeSettledInCash
Namespace Prefix:	smtc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested and Unsettled Units

+ References

No definition available.

+ Details

Name:	smtc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndUnsettledUnits
Namespace Prefix:	smtc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Share Based Compensation Arrangement Grants In Period Percentage Within Current Year

+ References

No definition available.

+ Details

Name:	smtc_ShareBasedCompensationArrangementGrantsInPeriodPercentageWithinCurrentYear
Namespace Prefix:	smtc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target performance metrics for performance unit awards, next fiscal year.

+ References

No definition available.

+ Details

Name:	smtc_ShareBasedCompensationArrangementGrantsInPeriodPercentageWithinNextYear
Namespace Prefix:	smtc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share Based Compensation Arrangement Grants In Period Percentage Within Previous Year

+ References

No definition available.

+ Details

Name:	smtc_ShareBasedCompensationArrangementGrantsInPeriodPercentageWithinPreviousYear
Namespace Prefix:	smtc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based compensation arrangement, performance condition, highest potential performance level

+ References

No definition available.

+ Details

Name:	smtc_Sharebasedcompensationarrangementperformanceconditionhighestpotentialperformancelevel
Namespace Prefix:	smtc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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