Discontinued Operations - Cash Flow Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 29, 2017	Sep. 30, 2016	Oct. 02, 2015
Operating activities:
Share-based compensation expense	$ 41.2	$ 48.3	$ 46.3
Depreciation	58.5	64.2	60.1
Amortization of intangible assets	18.4	15.6	8.4
Investing activities:
Purchases of property, plant & equipment	(59.1)	(80.4)	(91.4)
Sale of available-for-sale securities	0.0	8.6	0.6
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff
Operating activities:
Share-based compensation expense	2.0	6.1	6.4
Depreciation	4.8	10.5	10.5
Amortization of intangible assets	1.8	5.5	2.7
Investing activities:
Purchases of property, plant & equipment	(6.4)	(28.9)	(34.3)
Acquisition of business, net of cash acquired	0.0	(1.2)	(67.9)
Sale of available-for-sale securities	$ 0.0	$ 8.6	$ 0.0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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-Publisher FASB
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Net Cash Provided by (Used in) Investing Activities, Discontinued Operations [Abstract]

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