Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Sep. 28, 2019
Income Tax Contingency [Line Items]
Income tax expense	$ 5,822,000	$ 4,249,000	$ 9,262,000	$ 7,038,000
Effective tax rate	(8.20%)	36.50%	(13.50%)	35.70%
Statutory federal income tax rate	21.00%	35.00%	21.00%	35.00%
Change in uncertain tax positions	$ 0		$ (400,000)
Scenario Forecast [Member]
Income Tax Contingency [Line Items]
Change in uncertain tax positions					$ (200,000)

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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