Note 5 - Summary of Share-based Compensation Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 30, 2017	Dec. 24, 2016
Share-based compensation expense	$ 816	$ (36)
The above compensation is net of tax benefits	137	783
Employee Stock Option [Member]
Share-based compensation expense	615	(211)
Stock Purchase Plan [Member]
Share-based compensation expense	200	174
Restricted Stock [Member]
Share-based compensation expense	$ 1	$ 1

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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