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Income Taxes - Acquisition and integration expenses information (Details) - USD ($) | 12 Months Ended
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Oct. 01, 2017 | Oct. 02, 2016 | Sep. 27, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Effective tax rate (as a percent) | 31.30% | 32.60% | 51.20%
Effective income tax rate excluding R&D credits, acquisition expenses and debt pre-payment fees (as a percent) | 34.20% | 30.90% |
Tax benefit recognized based on IRS examination and settlement. | $ 1,200,000 |  |
Payments made to tax authorities | 23,000,000 |  |
Acquisition and integration expenses and debt pre-payment fees |  | $ 13,300,000 |
Income tax benefit on business combination acquisition and integration expenses and debt pre-payment fees |  | 0 |
Business combination acquisition related expenses |  | 6,400,000 |
Business combination integration costs and debt pre-payment fees |  | 6,900,000 |
R&D credits |  | $ 2,000,000 |
Accounting Standards Update 2016-09 |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Excess tax benefit | $ 4,900,000 |  |

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- Definition Amount 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 deduction of business combination and integration and debt pre-payment fees. + References No definition available. + Details
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- Definition Amount 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 nondeductible business combination acquisition related expenses. + References No definition available. + Details
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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