Note 13 - Income Taxes - Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 26, 2021	Sep. 27, 2020
Unrecognized tax benefits, balance	$ 27,008	$ 18,252
Changes in tax positions for prior years	1,008
Changes in tax positions for prior years		(331)
Increases (decrease) in tax positions for the current year	(8,940)
Increases (decrease) in tax positions for the current year		9,825
Lapse in statute of limitations	(797)	(738)
Unrecognized tax benefits, balance	$ 18,279	$ 27,008

Amount of unrecognized tax benefits.

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