Note 3 - Restructuring Charges - Summary of Restructuring Activities and Associated Costs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Jun. 30, 2018	Jul. 01, 2017
Liability, beginning of period		$ 97	$ 165	$ 270		$ 270
Restructuring charges		60	25	48		133
Cash payments		(139)	(93)	(153)
Liability, end of period		18	97	165		18
Equipment Relocation Costs [Member]
Liability, beginning of period				31		31
Restructuring charges		60	25	48
Cash payments		(60)	(25)	(79)
Liability, end of period
Employee Severance [Member]
Liability, beginning of period		97	165	239		239
Restructuring charges
Cash payments		(79)	(68)	(74)
Liability, end of period		$ 18	$ 97	$ 165		$ 18

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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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

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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://fasb.org/us-gaap/role/ref/legacyRef
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