Note 4 - Restructuring Charges - Charges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 27, 2026	Jun. 28, 2025	Jun. 27, 2026	Jun. 28, 2025
Restructuring Charges	$ 633	$ 1,210	$ 1,404	$ 7,838
Poway Volume Manufacturing Transition [Member]
Accrued restructuring, balance				0
Restructuring Charges				1,224
Amounts paid or charged				(583)
Accrued restructuring, balance		641		641
Poway Volume Manufacturing Transition [Member] \| Employee Severance [Member]
Accrued restructuring, balance				0
Restructuring Charges				766
Amounts paid or charged				(243)
Accrued restructuring, balance		523		523
Poway Volume Manufacturing Transition [Member] \| Other Restructuring [Member]
Accrued restructuring, balance				0
Restructuring Charges				458
Amounts paid or charged				(340)
Accrued restructuring, balance		118		118
2025 Strategic Restructuring [Member]
Accrued restructuring, balance			2,132	0
Restructuring Charges			1,403	6,615
Amounts paid or charged			(3,196)	(4,610)
Accrued restructuring, balance	338	2,409	338	2,409
Impact of currency exchange			(1)	404
2025 Strategic Restructuring [Member] \| Employee Severance [Member]
Accrued restructuring, balance			2,132	0
Restructuring Charges			774	6,559
Amounts paid or charged			(2,567)	(4,554)
Accrued restructuring, balance	338	2,409	338	2,409
Impact of currency exchange			(1)	404
2025 Strategic Restructuring [Member] \| Other Restructuring [Member]
Accrued restructuring, balance			0	0
Restructuring Charges			629	56
Amounts paid or charged			(629)	(56)
Accrued restructuring, balance	$ 0	$ 0	0	0
Impact of currency exchange			$ 0	$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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