FAIR VALUE - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jul. 03, 2020	Sep. 27, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity investment	$ 47.0
Available-for-sale securities	52.4	$ 58.8
Fair Value, Measurements, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	1.6	2.8
Total assets measured at fair value	225.0	61.8
Derivative liabilities	(0.1)
Contingent consideration	(65.4)	(75.3)
Total liabilities measured at fair value	(65.5)	(75.3)
Fair Value, Measurements, Recurring | MPTC Series B-1 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	24.4	27.1
Fair Value, Measurements, Recurring | MPTC Series B-2 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	22.7	25.1
Fair Value, Measurements, Recurring | APTC securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	5.3	6.6
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	0.0	0.0
Total assets measured at fair value	124.0	0.2
Derivative liabilities	0.0
Contingent consideration	0.0	0.0
Total liabilities measured at fair value	0.0	0.0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Instruments | MPTC Series B-1 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Instruments | MPTC Series B-2 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Instruments | APTC securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	1.6	2.8
Total assets measured at fair value	101.0	61.6
Derivative liabilities	(0.1)
Contingent consideration	0.0	0.0
Total liabilities measured at fair value	(0.1)	0.0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs | MPTC Series B-1 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	24.4	27.1
Fair Value, Measurements, Recurring | Significant Other Observable Inputs | MPTC Series B-2 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	22.7	25.1
Fair Value, Measurements, Recurring | Significant Other Observable Inputs | APTC securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	5.3	6.6
Fair Value, Measurements, Recurring | Significant Unobservable Inputs
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	0.0	0.0
Total assets measured at fair value	0.0	0.0
Derivative liabilities	0.0
Contingent consideration	(65.4)	(75.3)
Total liabilities measured at fair value	(65.4)	(75.3)
Fair Value, Measurements, Recurring | Significant Unobservable Inputs | MPTC Series B-1 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs | MPTC Series B-2 Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs | APTC securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	124.0	0.2
Equity investment	47.0
Fair Value, Measurements, Recurring | Money market funds | Quoted Prices in Active Markets for Identical Instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	124.0	0.2
Equity investment	0.0
Fair Value, Measurements, Recurring | Money market funds | Significant Other Observable Inputs
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0.0	0.0
Equity investment	47.0
Fair Value, Measurements, Recurring | Money market funds | Significant Unobservable Inputs
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0.0	$ 0.0
Equity investment	$ 0.0