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Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 01, 2018 | Dec. 31, 2017 | Jul. 02, 2017 | Apr. 02, 2017 | Apr. 01, 2018 | Jul. 01, 2018 | Jul. 02, 2017 | Sep. 30, 2018 | Oct. 01, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |  |
Effective tax rate (as a percent) |  |  |  |  |  | 20.00% | 30.40% |  |
Deferred tax benefit from tax reform remeasurement |  | $ 10,100 |  |  |  |  |  |  |
Effective income tax rate excluding revaluation of deferred taxes (as a percent) |  |  |  |  | 27.40% |  |  |  |
Incremental tax expense from disposition of business | $ 2,600 |  |  |  |  |  |  |  |
Goodwill written off related to sale of divested business | 12,200 |  |  |  |  | $ 12,160 |  |  |
Tax benefit recognized in connection with the IRS examination | 400 |  |  | $ 1,200 |  |  |  |  |
Payments made to tax authorities | 7,600 |  | $ 21,500 |  |  |  |  |  |
Effective income tax rate excluding excess tax benefit and TCJA impacts (as a percent) |  |  |  |  |  | 25.00% | 29.50% |  |
Liability for uncertain tax positions | 8,900 |  |  |  |  | $ 8,900 |  |  | $ 6,000
Period during which unrecognized tax benefits would affect the effective tax rate |  |  |  |  |  | 12 months |  |  |
Foreign Tax Authority |  |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |  |
Reserve for uncertain tax position in connection with IRS examination |  |  |  | $ 2,300 |  |  |  |  |
Scenario, Forecast |  |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |  |
Statutory federal tax rate |  |  |  |  |  |  |  | 24.50% |
Disposed of by sale | Non-core field services business |  |  |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |  |  |
Loss on disposition of business | $ 3,400 |  |  |  |  | $ 3,400 |  |  |

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