Debt (Schedule Of Debt) (Detail) - USD ($) $ in Millions	Sep. 27, 2019	Dec. 28, 2018
Debt Instrument [Line Items]
Total debt	$ 1,750.3	$ 1,968.5
Unamortized discount and issuance costs	(11.3)	(13.4)
Less: Short-term debt	236.3	256.2
Long-term debt	$ 1,514.0	1,712.3
Uncommitted Facilities, floating rate
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	1.93%
Total debt	$ 236.3	255.9
Promissory Notes And Other Debt
Debt Instrument [Line Items]
Promissory Notes and Other Debt, Current and Noncurrent	$ 0.3	1.0
2023 Senior Notes, 4.15%, due June 2023 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	4.36%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.15%
Debt Instrument, Principal	$ 300.0	300.0
2028 Senior Notes, 4.9%, due June 2028 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	5.04%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.90%
Debt Instrument, Principal	$ 600.0	600.0
2024 Senior Notes, 4.75%, due December 2024 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	4.95%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.75%
Debt Instrument, Principal	$ 400.0	400.0
Term Loan [Member] \| Term Loan, due May 2021 \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	3.54%
Total debt	$ 225.0	$ 425.0

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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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