FAIR VALUE - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 30, 2018	Sep. 29, 2017
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	$ 10.7	$ 60.1
DRTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		8.3
APTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	6.1
GPTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	4.6	4.4
Fair Value, Measurements, Recurring
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Derivative assets	0.5
Total assets measured at fair value	11.2	60.1
Derivative liabilities	(12.4)
Contingent consideration	(2.8)
Total liabilities measured at fair value	(15.2)
Fair Value, Measurements, Recurring \| Original CPTC loans
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		47.4
Fair Value, Measurements, Recurring \| DRTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		8.3
Fair Value, Measurements, Recurring \| APTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	6.1
Fair Value, Measurements, Recurring \| GPTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	4.6	4.4
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Instruments
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Derivative assets	0.0
Total assets measured at fair value	0.0	0.0
Derivative liabilities	0.0
Contingent consideration	0.0
Total liabilities measured at fair value	0.0
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Instruments \| Original CPTC loans
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		0.0
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Instruments \| DRTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		0.0
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Instruments \| APTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	0.0
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Instruments \| GPTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	0.0	0.0
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Derivative assets	0.5
Total assets measured at fair value	11.2	12.7
Derivative liabilities	(12.4)
Contingent consideration	0.0
Total liabilities measured at fair value	(12.4)
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs \| Original CPTC loans
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		0.0
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs \| DRTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		8.3
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs \| APTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	6.1
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs \| GPTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	4.6	4.4
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Derivative assets	0.0
Total assets measured at fair value	0.0	47.4
Derivative liabilities	0.0
Contingent consideration	(2.8)
Total liabilities measured at fair value	(2.8)
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs \| Original CPTC loans
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		47.4
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs \| DRTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities		0.0
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs \| APTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	0.0
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs \| GPTC Securities
Assets/Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale securities	$ 0.0	$ 0.0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Fair value of financial and nonfinancial obligations.

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Contingent Consideration Liability, Fair Value

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