Income Taxes [Line Items]

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- Definition

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit), Alternative Minimum Tax Credits

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense

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Tax Cuts And Jobs Act of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Liability, Current

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- Definition

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Apr. 01, 2018	Dec. 31, 2017	Apr. 02, 2017	Apr. 01, 2018	Apr. 02, 2017	Sep. 30, 2018
Income Taxes [Line Items]
Provision for income taxes	$ 15.6		$ 1.7	$ 2.0	$ 10.9
Provisional Income Tax Expense (Benefit)	11.1	$ (12.4)
Alternative minimum tax credits	11.8
Provisional income tax expense in earnings of certain foreign subsidiaries	13.1
Uncertain tax positions	2.0			2.0
Unrecognized tax benefit that would impact effective tax rate within next twelve months	$ 1.0			$ 1.0
Minimum \| Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax years by major tax jurisdiction				2007
Maximum \| Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax years by major tax jurisdiction				2016
Forecast
Income Taxes [Line Items]
U.S. statutory rate						24.50%