Income Taxes (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	Dec. 22, 2017	Oct. 01, 2017	Mar. 31, 2018	Apr. 01, 2017	Mar. 31, 2018	Apr. 01, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate			45.60%	34.30%	79.20%	27.10%
U.S. federal corporate tax rate	21.00%	35.00%
Transition Tax on Undistributed Foreign Earnings Deemed To Be Repatriated					$ 31,300
Withholding Taxes on Undistributed Foreign Earnings Deemed To Be Repatriated					15,910
Additional Income Tax Provision For Remaining Undistributed Foreign Earnings					0
Income tax benefit due to remeasurement of deferred tax assets and liabilities					$ 8,966