The yearly percentage of grants tested for award vesting rights under share based payment arrangement.

No definition available.

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Namespace Prefix:	lscc_
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Balance Type:	na
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- Definition

The percentage of market condition achieved for awards to vest under share based payment arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	lscc_
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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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- Details

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Note 9 - Stock-based Compensation (Details Textual) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 28, 2020	Mar. 30, 2019	Dec. 28, 2019
Share-based Payment Arrangement, Expense	$ 8,728	$ 3,686
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	1,800
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member]
Share-based Payment Arrangement, Expense	$ 4,200		$ 900
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Grants Tested Each Year	33.33%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved	75.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved	75.00%
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member] \| Share-based Payment Arrangement, Tranche One [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	250.00%
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member] \| Share-based Payment Arrangement, Tranche One [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved	55.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
Restricted Stock Units (RSUs) [Member] \| Executive Officer [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved	25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%