Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 24, 2016	Sep. 26, 2015
Deferred tax assets [Abstract]
Net operating loss carryforwards	$ 60,628	$ 55,033
Allowance for doubtful accounts	184	340
Inventory	457	395
Deferred revenue	1,091	1,241
Derivative instruments	78	0
AMT credit carryforward	1,086	1,086
Other accruals	1,101	1,718
Total deferred tax assets	64,625	59,813
Deferred tax liabilities [Abstract]
Derivative instruments	0	142
Intangible assets	775	312
Property, plant and equipment	5,068	5,314
Total deferred tax liabilities	5,843	5,768
Net deferred tax assets	58,782	54,045
Valuation allowance	(58,782)	(54,045)
Net deferred tax assets	$ 0	$ 0