Note 3 - Goodwill and Purchased Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019
Gross Carrying Amount, finite-lived intangible assets	$ 338,279	$ 322,804
Accumulated Amortization	112,412	68,617
Developed Technology Rights [Member]
Gross Carrying Amount, finite-lived intangible assets	239,250	227,619
Accumulated Amortization	$ 83,246	49,805
Remaining Useful Life (Year)	5 years 8 months 12 days
Customer Relationships [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 74,933	72,251
Accumulated Amortization	$ 22,751	14,824
Remaining Useful Life (Year)	8 years 6 months
Trade Names [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 23,756	22,612
Accumulated Amortization	$ 6,279	3,892
Remaining Useful Life (Year)	8 years 8 months 12 days
Noncompete Agreements [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 340	322
Accumulated Amortization	$ 136	$ 96
Remaining Useful Life (Year)	6 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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