Other Financial Information - Components of Other Long-Term Liabilities (Detail) - USD ($) $ in Millions	Sep. 27, 2019	Sep. 28, 2018
Other Financial Information [Abstract]
Income taxes payable	$ 180.3	$ 189.1
Deferred revenues	73.1	38.6
Deferred income taxes	75.3	31.4
Contingent consideration	42.3	23.2
Defined benefit pension plans	31.1	8.6
Other	38.0	33.4
Total other long-term liabilities	$ 440.1	$ 324.3

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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