Income Tax Examinations by Tax Authorities in its Major Tax Jurisdictions (Detail)	12 Months Ended
	Sep. 28, 2018
U.S. Federal
Income Tax Examination [Line Items]
Income Tax Examination, Years No Longer Subject To Audit	2014 and prior
Belgium
Income Tax Examination [Line Items]
Income Tax Examination, Years No Longer Subject To Audit	2015 and prior
Canada
Income Tax Examination [Line Items]
Income Tax Examination, Years No Longer Subject To Audit	2010 and prior
France
Income Tax Examination [Line Items]
Income Tax Examination, Years No Longer Subject To Audit	2013 and prior
United Kingdom
Income Tax Examination [Line Items]
Income Tax Examination, Years No Longer Subject To Audit	2015 and prior