Income Taxes - Activity Related to Company's Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands |
12 Months Ended | |
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Sep. 30, 2017 |
Sep. 24, 2016 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | ||
| Beginning Balance | $ 254 | $ 138 |
| Increases related to prior year tax positions | 4 | 51 |
| Increases related to current year tax positions | 67 | 66 |
| Decreases related to prior year tax positions | 0 | 0 |
| Settlements | 0 | (1) |
| Decreases related to lapse of statute of limitations | 0 | 0 |
| Ending Balance | $ 325 | $ 254 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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