Represents the maximum amount of the guarantees available through letters of credit.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Represents the amount that the borrowing capacity of the line of credit may be increased at the entity's option, subject to certain conditions, under the terms of the credit agreement.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the maximum ratio of total debt to earnings before interest expense, income taxes and noncash items (such as depreciation, depletion and amortization expense, unrealized gains and losses on commodity derivatives, ceiling test write-downs, and goodwill impairments) permitted under credit facilities' covenants.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum ratio of earnings before interest expense, income taxes and noncash items (such as depreciation, depletion and amortization expense, unrealized gains and losses on commodity derivatives, ceiling test write-downs, and goodwill impairments) to debt payment permitted under credit facilities' covenants.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Represents the maximum amount of the guarantees available through swingline loan.

+ References

No definition available.

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

Reference 3: 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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:	credit
Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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Data Type:	na
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- Details

Name:	us-gaap_CreditFacilityAxis=slab_RevolvingCreditFacilityOtherThanSwinglineLoansMember
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- Details

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Debt - Amended Credit Agreement (Details) $ in Millions				9 Months Ended
Debt - Amended Credit Agreement (Details) $ in Millions	Feb. 27, 2017 USD ($)	Jul. 24, 2015 USD ($)	Jul. 31, 2012 USD ($)	Sep. 30, 2017
Credit Agreement
Debt
Maximum borrowing capacity			$ 230.0
Term of debt instrument			5 years
Amount borrowed under the Amended Credit Agreement		$ 82.5
Revolving Credit Facility
Debt
Maximum borrowing capacity		$ 300.0	$ 130.0
Term of debt instrument		5 years
Sublimit on letters of credit	$ 25.0
Sublimit on swingline loan	10.0
Additional increase in borrowing capacity of the line of credit available at the entity's option	200.0
Amended Credit Agreement
Debt
Repayment of credit facility amount	$ 72.5
Maximum leverage ratio				3.00
Minimum fixed charge coverage ratio				1.25
Revolving credit facility, other than swingline loans \| Federal Funds
Debt
Interest rate added to the base rate (as a percent)				0.50%
Revolving credit facility, other than swingline loans \| Eurodollar base rate
Debt
Interest rate added to the base rate (as a percent)				1.00%
Revolving credit facility, other than swingline loans \| Eurodollar \| Low end of range
Debt
Interest rate added to the base rate (as a percent)				1.25%
Revolving credit facility, other than swingline loans \| Eurodollar \| High end of range
Debt
Interest rate added to the base rate (as a percent)				2.00%
Term loan facility, revolving credit facility, swingline and other loans \| Base rate \| Low end of range
Debt
Interest rate added to the base rate (as a percent)				0.25%
Term loan facility, revolving credit facility, swingline and other loans \| Base rate \| High end of range
Debt
Interest rate added to the base rate (as a percent)				1.00%
Term Loan Facility
Debt
Maximum borrowing capacity			$ 100.0