Income Taxes - Reconciliation of the Statutory Federal Income Tax Rate to the Company's Effective Income Tax Rate (Detail) |
12 Months Ended | ||
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Sep. 30, 2017 |
Sep. 24, 2016 |
Sep. 26, 2015 |
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| Income Tax Disclosure [Abstract] | |||
| Statutory federal income tax rate | 35.00% | 35.00% | 35.00% |
| State income taxes, net of federal benefit | 2.40% | 2.10% | 2.40% |
| Other permanent differences | 0.30% | (1.60%) | (0.50%) |
| Adjustment of prior year accruals | (0.30%) | (0.60%) | (0.50%) |
| Credits | (0.60%) | (1.00%) | (0.30%) |
| Change in valuation allowances | 0.00% | 0.50% | 0.00% |
| Foreign rate differential | 0.10% | 0.10% | (0.10%) |
| Effective income tax rate (benefit) | 36.90% | 34.50% | 36.00% |
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- Definition Effective income tax rate reconciliation permanent differences. No definition available.
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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