v3.7.0.1

Debt (Schedule Of Debt) (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 30, 2016
Debt Instrument [Line Items]
Total debt	$ 612.3	$ 619.9
Less: Short-term debt	147.3	130.3
Long-term debt	465.0	489.6
Uncommitted Facilities [Member]
Debt Instrument [Line Items]
Total debt	147.0	130.0
Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	400.0	400.0
Unamortized discount on Notes	(2.3)	(2.5)
Debt issuance costs	(2.3)	(2.4)
Note Payable Fair Value	431.0	410.6
Promissory Notes And Other Debt [Member]
Debt Instrument [Line Items]
Principal amount	0.6	0.5
Total debt	0.9	0.8
Note Payable Fair Value	0.9	0.8
2014 Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	$ 69.0	$ 94.0

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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 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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