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FAIR VALUE - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 03, 2020	Mar. 29, 2019	Apr. 03, 2020	Mar. 29, 2019	Sep. 27, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charge	$ 40.5	$ 0.0	$ 40.5	$ 0.0
Equity investments in privately-held companies	56.4		56.4		$ 64.2
Notes Receivable
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-term notes receivable	34.9		34.9		33.6
C P T C
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charge	40.5
C P T C \| Term Loan
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of financing receivable	$ 4.7		$ 4.7		$ 45.2
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative, term of contract			1 month
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative, term of contract			15 months