Balance Sheet Components - Components of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Millions	Sep. 28, 2018	Sep. 29, 2017
Balance Sheet Related Disclosures [Abstract]
Prepaid income taxes	$ 48.1	$ 59.9
Available-for-sale securities	39.4	0.0
RPTC secured debt	24.9	25.4
Prepaid compensation	14.2	11.6
Advance payments to suppliers	16.6	14.9
Other current receivables	24.1	28.7
Other prepaid expenses	66.0	49.8
Total prepaid expenses and other current assets	$ 233.3	$ 190.3

Carrying value of capitalized payments made in advance for inventory that is expected to be received within one year or the normal operating cycle, if longer.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for income and other taxes that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Prepaid Compensation Expense, Current

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Senior Secured Debt, Current

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