Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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FAIR VALUE - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Mar. 30, 2018	Dec. 06, 2017	Sep. 29, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying value of long-term debt	$ 25.0		$ 0.0
Fair Value	10.7		60.1
Notes Receivable
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-term	$ 62.6		100.2
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Remaining maturity	1 month
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Remaining maturity	13 months
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying value of long-term debt	$ 25.0
C P T C \| Term Loan
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Modified former loans receivable	$ 44.0		$ 0.0
Varian Medical Systems, Inc. \| C P T C \| Term Loan
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Modified former loans receivable		$ 53.5