Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum

No definition available.

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- Definition

Debt Instrument, Fronting Fee

+ References

No definition available.

+ Details

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Namespace Prefix:	smtc_
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Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	smtc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ 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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details)		3 Months Ended
Subsequent Events (Details)	Nov. 07, 2019 USD ($)	Jan. 26, 2020 USD ($)	Oct. 27, 2019 USD ($)	Nov. 15, 2016 USD ($)
Revolving loans
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity				$ 250,000,000.0
Undrawn revolving commitments			$ 153,000,000.0
Revolving loans \| Subsequent Event
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity	$ 600,000,000
Line of Credit \| Fed Funds \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	0.50%
Line of Credit \| One month LIBOR \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	1.00%
Line of Credit \| Minimum \| Base Rate \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	0.25%
Line of Credit \| Minimum \| LIBOR \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	1.25%
Line of Credit \| Maximum \| Base Rate \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	1.25%
Line of Credit \| Maximum \| LIBOR \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument margin	2.25%
Line of Credit \| Revolving loans
Subsequent Event [Line Items]
Unused facility fee	0.20%
Line of Credit \| Revolving loans \| Subsequent Event
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity	$ 600,000,000.0
Increase to the principal amount	$ 300,000,000
Consolidated leverage ratio, maximum	3.00
Line of Credit \| Revolving loans \| Minimum
Subsequent Event [Line Items]
Unused facility fee	0.20%
Line of Credit \| Revolving loans \| Maximum
Subsequent Event [Line Items]
Unused facility fee	0.35%
Line of Credit \| Letter of Credit \| Subsequent Event
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity	$ 40,000,000.0
Fronting Fee	0.125%
Line of Credit \| Swing Line Loans \| Subsequent Event
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity	$ 25,000,000.0
Line of Credit \| Revolving loans and letters of credit in alternative currencies \| Subsequent Event
Subsequent Event [Line Items]
Facilities, maximum borrowing capacity	$ 40,000,000.0
Forecast \| Subsequent Event
Subsequent Event [Line Items]
Write off of deferred debt issuance cost		$ 500,000
Forecast \| Line of Credit \| Revolving loans \| Subsequent Event
Subsequent Event [Line Items]
Proceeds from lines of credit		201,000,000
Repayments of lines of credit		97,000,000
Undrawn revolving commitments		399,000,000
Forecast \| Term loan \| Subsequent Event
Subsequent Event [Line Items]
Repayments of long-term debt		$ 101,300,000