Taxes on Earnings - Schedule of Taxes on Earnings (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Current provision:
Federal	$ 188.3	$ 30.9	$ 56.0
State and local	8.0	4.3	7.3
Foreign	47.9	67.5	75.4
Total current	244.2	102.7	138.7
Deferred provision (benefit):
Federal	43.7	(18.3)	(17.4)
State and local	(3.3)	(0.2)	(1.7)
Foreign	17.2	(7.1)	(9.5)
Total deferred	57.6	(25.6)	(28.6)
Taxes on earnings	$ 301.8	$ 77.1	$ 110.1

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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