Note 6 - Stock-based Compensation - Restricted Stock and Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares shares in Thousands	3 Months Ended	6 Months Ended
Apr. 01, 2017	Apr. 02, 2016	Apr. 01, 2017	Apr. 02, 2016
Restricted stock units outstanding, beginning balance (in shares)			145
Weighted average grant date fair value, beginning balance (in dollars per share)			$ 22.35
Restricted stock units outstanding, Granted (in shares)	19	43	19	43
Weighted average grant date fair value, Granted (in dollars per share)			$ 37.06
Restricted stock units outstanding, released (in shares)			(31)
Weighted average grant date fair value, released (in dollars per share)			$ 20.39
Restricted stock units outstanding, ending balance (in shares)	133		133
Weighted average grant date fair value, ending balance (in dollars per share)	$ 24.88		$ 24.88

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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