Business acquisition pro forma information earnings adjusted for amortization of acquired intangible assets.

No definition available.

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- Definition

In-process research and development, estimated percent complete.

+ References

No definition available.

+ Details

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- Definition

In-process research and development, estimated remaining cost to complete project.

+ References

No definition available.

+ Details

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Namespace Prefix:	qlgc_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

In-process research and development, estimated remaining time to complete project.

+ References

No definition available.

+ Details

Name:	qlgc_InProcessResearchAndDevelopmentEstimatedRemainingTimeToCompleteProject
Namespace Prefix:	qlgc_
Data Type:	xbrli:durationItemType
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- Definition

The fee paid for a non-exclusive patent license agreement.

+ References

No definition available.

+ Details

Name:	qlgc_PatentLicenseAgreement
Namespace Prefix:	qlgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The portion of a license payment the Company attributed to the future use of the related technology.

+ References

No definition available.

+ Details

Name:	qlgc_PatentLicenseAgreementFuturePeriods
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Data Type:	xbrli:monetaryItemType
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- Definition

The portion of a license payment the Company attributed to the use of the related technology in periods prior to the date of the license agreement.

+ References

No definition available.

+ Details

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

- Definition

The term of a patent license the Company attributed to the future use of the related technology.

+ References

No definition available.

+ Details

Name:	qlgc_PatentLicenseAgreementTerm
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Period Type:	duration

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, 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 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Details

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

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1500-128463

+ Details

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

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

+ Details

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

- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The amount of inventory recognized as of the acquisition date.

+ References

+ Details

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

- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

+ Details

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

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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Balance Type:	credit
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- Details

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- Details

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Business Acquisitions and License Agreement - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended			1 Months Ended
	Mar. 30, 2014	Mar. 30, 2014	Mar. 30, 2014	Mar. 31, 2013	Mar. 29, 2015	Jan. 31, 2014
Business Acquisition [Line Items]
Business acquisition, cash consideration			$ 157,352,000
Amortization expense related to acquired intangible assets			12,000,000	12,000,000
Patent license agreement	62,000,000qlgc_PatentLicenseAgreement	62,000,000qlgc_PatentLicenseAgreement	62,000,000qlgc_PatentLicenseAgreement
Patent license agreement, prior periods	41,000,000qlgc_PatentLicenseAgreementPriorPeriods	41,000,000qlgc_PatentLicenseAgreementPriorPeriods	41,040,000qlgc_PatentLicenseAgreementPriorPeriods
Patent license agreement, future periods	21,000,000
Patent license agreement term	10 years
Broadcom 10/40/100Gb Ethernet Business [Member]
Business Acquisition [Line Items]
Business acquisition, cash consideration	147,800,000
Business combination adjustment to identifiable intangible assets	25,300,000				25,300,000
Business combination adjustment to property and equipment	1,600,000				1,600,000
Estimated percentage of project complete	40.00%	40.00%	40.00%
Estimated remaining cost to complete project	6,000,000	6,000,000	6,000,000
Estimated remaining time to complete project	2 years
Business acquisition, purchase price allocation to inventory	2,880,000	2,880,000	2,880,000
Broadcom 10/40/100Gb Ethernet Business [Member] \| Property and Equipment [Member]
Business Acquisition [Line Items]
Business combination adjustment to goodwill	(1,600,000)				(1,600,000)
Broadcom 10/40/100Gb Ethernet Business [Member] \| Identifiable Intangible Assets [Member]
Business Acquisition [Line Items]
Business combination adjustment to goodwill	(25,300,000)				(25,300,000)
Broadcom 10/40/100Gb Ethernet Business [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Risk adjusted discount rates	14.50%
Broadcom 10/40/100Gb Ethernet Business [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Risk adjusted discount rates	17.00%
Brocade Communications Systems, Inc. [Member]
Business Acquisition [Line Items]
Business acquisition, cash consideration						9,600,000
Business acquisition, purchase price allocation to inventory						1,700,000
Business acquisition, purchase price allocation to identifiable intangible assets						$ 8,000,000
Brocade Communications Systems, Inc. [Member] \| Developed Technology [Member]
Business Acquisition [Line Items]
Estimated useful life of purchased intangible assets						4 years