Interest Coverage Ratio

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- Definition

Prior credit facilities, repayment of outstanding obligations

+ References

No definition available.

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- Definition

Total Leverage Ratio

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

Amount of the required periodic payments applied to principal.

+ References

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

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- 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

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

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Credit Facilities - Narrative (Details)				9 Months Ended
Credit Facilities - Narrative (Details)	Oct. 23, 2015 USD ($)	Mar. 04, 2015 USD ($)	May. 02, 2013 USD ($)	Oct. 25, 2015 USD ($)	Oct. 26, 2014 USD ($)
Facilities, maximum borrowing capacity			$ 400,000,000
Facilities, amount outstanding			326,600,000
Facilities, debt discount			1,400,000
Prior credit facilities, repayment of outstanding obligations			$ 327,500,000
Borrowings under line of credit		$ 35,000,000		$ 35,000,000	$ 0
Minimum [Member]
Interest coverage ratio				3.50
Maximum [Member]
Total leverage ratio				3.00
Base Rate [Member]
Description of variable rate basis			the highest of (a) the prime rate (as published by The Wall Street Journal), (b) ½ of 1% above the federal funds effective rate or (c) one-month LIBOR (determined with respect to deposits in U.S. Dollars) plus 1%.
Base Rate [Member] \| Minimum [Member]
Basis spread on variable rate			0.25%
Base Rate [Member] \| Maximum [Member]
Basis spread on variable rate			1.25%
LIBOR [Member]
Basis spread on variable rate			1.00%
LIBOR [Member] \| Minimum [Member]
Basis spread on variable rate			1.25%
LIBOR [Member] \| Maximum [Member]
Basis spread on variable rate			2.25%
Federal Funds [Member]
Basis spread on variable rate			1.00%
CDOR [Member]
Description of variable rate basis			the sum of: (a) the rate determined by Administrative Agent with reference to the arithmetic average of the discount rate quotations of all institutions listed for CAD Dollar-denominated bankers’ acceptances displayed and identified on the “Reuters Screen CDOR Page” and (b) 0.10% per annum
Basis spread on variable rate			0.10%
CDOR [Member] \| Minimum [Member]
Basis spread on variable rate			1.25%
CDOR [Member] \| Maximum [Member]
Basis spread on variable rate			2.25%
Term Loans [Member]
Facilities, maximum borrowing capacity			$ 150,000,000
Facilities, amount outstanding			149,300,000	$ 81,800,000
Facilities, Interest rate at period end				2.07%
Principal payments remaining in fiscal year 2016				$ 4,700,000
Principal payments in fiscal year 2017				18,800,000
Principal payments in fiscal year 2018				24,400,000
Repayments of debt	$ 12,000,000
Revolving Commitments [Member]
Facilities, maximum borrowing capacity			250,000,000
Facilities, amount outstanding			$ 177,300,000	$ 181,000,000
Facilities, Interest rate at period end				2.07%
Revolving Commitments [Member] \| Minimum [Member]
Facilities, unused capacity, commitment fee percentage			0.20%
Revolving Commitments [Member] \| Maximum [Member]
Facilities, unused capacity, commitment fee percentage			0.45%
Letter of Credit [Member]
Facilities, maximum borrowing capacity			$ 40,000,000
Facilities, amount outstanding				$ 0
Swingline Loans [Member]
Facilities, maximum borrowing capacity			25,000,000
Facilities, amount outstanding				0
Additional Term Loan or Increase in Revolver [Member]
Facilities, maximum borrowing capacity			$ 100,000,000
Alternative Currencies, Except Canadian [Member]
Description of variable rate basis			a rate per annum equal to LIBOR (determined with respect to deposits in the applicable Alternative Currency) for an interest period to be selected by Semtech plus a margin ranging from 1.25% to 2.25% depending upon Semtech’s consolidated leverage ratio.
Alternative Currencies Line of Credit [Member]
Facilities, maximum borrowing capacity			$ 40,000,000
Facilities, amount outstanding				0
United States of America, Dollars
Description of variable rate basis			(1) the Base Rate plus a margin ranging from 0.25% to 1.25% depending upon Semtech’s consolidated leverage ratio or (2) LIBOR (determined with respect to deposits in U.S. Dollars) for an interest period to be selected by Semtech plus a margin ranging from 1.25% to 2.25% depending upon Semtech’s consolidated leverage ratio.
Canada, Dollars
Description of variable rate basis			a rate per annum equal to the CDOR Rate for an interest period to be selected by Semtech plus a margin ranging from 1.25% to 2.25% depending upon Semtech’s consolidated leverage ratio.
Through second quarter of fiscal year 2018 [Domain] \| Term Loans [Member]
Facilities, required quarterly principal payment				4,700,000
Beginning third quarter of fiscal year 2018 [Domain] \| Term Loans [Member]
Facilities, required quarterly principal payment				$ 7,500,000