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Amount of available-for-sale debt securities at fair value maturing after the fifth rolling twelve months following the latest balance sheet presented.

No definition available.

Name:	qlgc_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearFiveFairValue
Namespace Prefix:	qlgc_
Data Type:	xbrli:monetaryItemType
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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the fourth rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented. Adjustments include, but are not limited to, accretion, amortization, collection of cash and previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined).

No definition available.

Name:	qlgc_AvailableForSaleSecuritiesDebtMaturitiesRollingYearFourThroughFiveAmortizedCostBasis
Namespace Prefix:	qlgc_
Data Type:	xbrli:monetaryItemType
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Amount of available-for-sale debt securities at fair value maturing in the fourth rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented.

No definition available.

Name:	qlgc_AvailableForSaleSecuritiesDebtMaturitiesRollingYearFourThroughFiveFairValue
Namespace Prefix:	qlgc_
Data Type:	xbrli:monetaryItemType
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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second rolling twelve months through the third rolling twelve months following the latest balance sheet presented. Adjustments include, but are not limited to, accretion, amortization, collection of cash and previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined).

No definition available.

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

Amount of available-for-sale debt securities at fair value maturing in the second rolling twelve months through the third rolling twelve months following the latest balance sheet presented.

No definition available.

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

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Fair value of available-for-sale debt securities maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26626-111562