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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Dec. 30, 2018 | Jun. 28, 2020 | Jun. 30, 2019 | Sep. 29, 2019
Valuation Allowance [Line Items] |  |  |  |  |
Effective tax rate |  |  | 21.20% | 7.10% |
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Amount |  |  | $ 7.1 | $ 4.3 |
Tax Cuts and Jobs Act, change in tax rate, income tax benefit |  | $ 2.6 |  |  |
Effective Income Tax Rate Reconciliation, Excluding Excess Tax Benefits On Share-based Payments, Tax Cuts And Jobs Act And Valuation Allowance Release Impacts, Percent |  |  | 25.50% | 25.50% |
Liability for uncertain tax positions |  |  | $ 9.3 |  | $ 9.2
AUSTRALIA |  |  |  |  |
Valuation Allowance [Line Items] |  |  |  |  |
Valuation allowance release | $ 22.3 |  |  |  |

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- Definition Amount recognized for uncertainty in income taxes. + 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/disclosureRef -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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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120384911&loc=d3e23163-113944 + Details
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