Note 2 - Goodwill and Purchased Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 27, 2021	Dec. 26, 2020
Gross Carrying Amount, finite-lived intangible assets	$ 336,149	$ 338,279
Accumulated Amortization	118,907	112,412
Developed Technology Rights [Member]
Gross Carrying Amount, finite-lived intangible assets	238,892	239,250
Accumulated Amortization	$ 88,305	83,246
Remaining Useful Life (Year)	5 years 3 months 18 days
Customer Relationships [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 73,691	74,933
Accumulated Amortization	$ 23,803	22,751
Remaining Useful Life (Year)	8 years 2 months 12 days
Trade Names [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 23,245	23,756
Accumulated Amortization	$ 6,662	6,279
Remaining Useful Life (Year)	8 years 6 months
Noncompete Agreements [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 321	340
Accumulated Amortization	$ 137	$ 136
Remaining Useful Life (Year)	5 years 9 months 18 days

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.

+ Details

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Data Type:	xbrli:durationItemType
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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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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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