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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Apr. 01, 2018 | Dec. 31, 2017 | Jul. 02, 2017 | Apr. 02, 2017 | Apr. 01, 2018 | Apr. 02, 2017 | Sep. 30, 2018 | Oct. 01, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |
Effective tax rate (as a percent) |  |  |  |  | 11.00% | 30.40% |  |
Deferred tax benefit from tax reform remeasurement |  | $ 10.1 |  |  |  |  |  |
Effective income tax rate excluding revaluation of deferred taxes (as a percent) |  |  |  |  | 23.00% |  |  |
Tax benefit recognized in connection with the IRS examination |  |  |  | $ 1.2 |  |  |  |
Payments made to tax authorities |  |  | $ 20.0 |  |  |  |  |
Effective income tax rate excluding excess tax benefit and TCJA impacts (as a percent) |  |  |  |  | 28.50% | 32.50% |  |
Liability for uncertain tax positions | $ 6.3 |  |  |  | $ 6.3 |  |  | $ 6.0
Period during which unrecognized tax benefits would affect the effective tax rate |  |  |  |  | 12 months |  |  |
Accounting Standards Update 2016-09 |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |
Excess tax benefit | $ 1.4 |  |  | 0.9 | $ 4.6 | $ 2.7 |  |
Scenario, Forecast |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |
Statutory federal tax rate |  |  |  |  |  |  | 24.50% |
Foreign Tax Authority |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |
Reserve for uncertain tax position in connection with IRS examination |  |  |  | $ 2.3 |  |  |  |

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