Note 12 - Changes to the Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Balance	$ 785,115	$ 722,182	$ 759,091	$ 682,322
Balance	809,667	738,075	809,667	738,075
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(13,044)	(11,330)	(12,079)	(9,341)
Other comprehensive income (loss) before reclassifications	496	(2,359)	(469)	(4,348)
Amounts reclassified from accumulated other comprehensive income	0	0	0	0
Balance	(12,548)	(13,689)	(12,548)	(13,689)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	0	172	85	466
Other comprehensive income (loss) before reclassifications	0	(328)	0	(622)
Amounts reclassified from accumulated other comprehensive income	0	75	(85)	75
Balance	0	(81)	0	(81)
AOCI Attributable to Parent [Member]
Balance	(13,044)	(11,158)	(11,994)	(8,875)
Other comprehensive income (loss) before reclassifications	496	(2,687)	(469)	(4,970)
Amounts reclassified from accumulated other comprehensive income	0	75	(85)	75
Balance	$ (12,548)	$ (13,770)	$ (12,548)	$ (13,770)

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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