Note 2 - Goodwill and Purchased Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2022	Dec. 25, 2021	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Goodwill, Impairment Loss	$ 0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			$ 0	$ 100	$ 11,249
Amortization of Intangible Assets			33,185	$ 35,414	$ 38,746
Finite-Lived Intangible Asset, Expected Amortization, Year One	33,400		33,400
Finite-Lived Intangible Asset, Expected Amortization, Year Two	33,400		33,400
Finite-Lived Intangible Asset, Expected Amortization, Year Three	24,800		24,800
Finite-Lived Intangible Asset, Expected Amortization, Year Four	18,600		18,600
Finite-Lived Intangible Asset, Expected Amortization, Year Five	15,100		15,100
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	$ 14,800		$ 14,800
Indefinite-lived In Process Research and Development [Member]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		$ 100

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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