This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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No definition available.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Quarterly Statement of Operations Information (Unaudited) - (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended							12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Sep. 24, 2016	Mar. 26, 2016	Dec. 26, 2015	Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Quarterly Financial Information Disclosure [Abstract]
Restructuring charges	$ 2.5	$ 6.0	$ 1.6	$ 3.2	$ 2.9	$ 3.8	$ 2.3	$ 13.3	$ 10.5	$ 28.5
Acquisition charges			19.4	$ 2.6
Gain on sale of investments			$ 899.7				$ 25.1	5.6	25.1	0.0
Debt extinguishment loss	$ (0.6)	$ 2.6			0.8	$ 4.5		3.2	$ 5.3	$ 62.7
Gain on sale of cost-method investments								$ 2.0
Other-than-temporary impairment charge					$ 1.1