Note 2 - Goodwill and Purchased Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 25, 2022	Dec. 25, 2021
Gross Carrying Amount, finite-lived intangible assets	$ 306,748	$ 316,232
Accumulated Amortization	150,951	138,912
Developed Technology Rights [Member]
Gross Carrying Amount, finite-lived intangible assets	222,240	229,131
Accumulated Amortization	$ 114,503	104,855
Remaining Useful Life (Year)	4 years
Customer Relationships [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 64,027	65,916
Accumulated Amortization	$ 27,939	26,189
Remaining Useful Life (Year)	7 years
Trade Names [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 20,220	20,877
Accumulated Amortization	$ 8,366	7,714
Remaining Useful Life (Year)	6 years 9 months 18 days
Noncompete Agreements [Member]
Gross Carrying Amount, finite-lived intangible assets	$ 261	308
Accumulated Amortization	$ 143	$ 154
Remaining Useful Life (Year)	4 years 6 months