Weighted-Average Stock Options and Warrants Outstanding Not included in Computation of Diluted Shares Outstanding (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Jul. 01, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Long-term Debt	$ 3,810.2			$ 3,810.2		$ 3,805.7
Preferred Stock Par Value Per Share	$ 2.5			$ 2.5		$ 2.50
Debt instrument, face amount	$ 3,840.0			$ 3,840.0
Payments for Repurchase of Common Stock	$ 301.8	$ 0.6		$ 514.5	$ 16.2
Common Stock, Shares, Issued	176,902,738			176,902,738		176,902,738
Equity Units Conversion Rate Number Of Common Stock Shares			0.7241	0.7255

Equity Units Conversion Rate Number Of Common Stock Shares

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Face (par) amount of debt instrument at time of issuance.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow to reacquire common stock during the period.

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