Segment Information - Reconciliation of Segment Gross Profit (Details) - USD ($) $ in Thousands		12 Months Ended
Dec. 12, 2016	Sep. 29, 2018	Sep. 30, 2017	Oct. 01, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment gross profit		$ 121,988	$ 127,368	$ 129,356
Selling, general and administrative expenses		(88,755)	(72,831)	(102,711)
Interest expense		(6,661)	(7,251)	(16,412)
Interest income		70	140	133
Other income (expense), net		231	66	(539)
Loss on debt extinguishment	$ (10,100)	0	(10,142)	0
Income before income taxes		26,873	37,350	9,827
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment gross profit		121,988	127,368	129,356
Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Selling, general and administrative expenses		(88,755)	(72,831)	(102,711)
Interest expense		(6,661)	(7,251)	(16,412)
Interest income		70	140	133
Other income (expense), net		$ 231	$ 66	$ (539)

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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