Taxes on Income (Significant Components of the Company's Net Deferred Tax Asset) (Details) (USD $) In Millions, unless otherwise specified	Jan. 03, 2015	Dec. 28, 2013	Apr. 24, 2013
Deferred tax assets:
Pension liability	$ 391.4	$ 279.8
Workers’ compensation and other claims	184.3	152.0
Employee benefits	165.1	155.7
Accrued claims and other liabilities	90.4	92.4
Reserves not currently deductible	77.3	63.8
Federal deduction of state taxes	3.5us-gaap_DeferredTaxAssetsStateTaxes	51.2us-gaap_DeferredTaxAssetsStateTaxes
State tax credit carryforwards	21.7	21.3
Operating loss carryforwards	0	8.8
Other assets	45.6us-gaap_DeferredTaxAssetsOther	9.5us-gaap_DeferredTaxAssetsOther
Deferred tax assets	979.3us-gaap_DeferredTaxAssetsGross	834.5us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities:
Property	(546.8)	(430.0)
Inventory	(311.7)	(273.3)
Investment in Blackhawk	0	(17.9)	(17.9)
Investments in foreign operations	(10.9)	(6.5)
Deferred tax liabilities, total	(869.4)us-gaap_DeferredIncomeTaxLiabilities	(727.7)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset	$ 109.9us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 106.8us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Liabilities, Investments in Foreign Noncontrolled Affiliates

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Deferred Tax Liabilities, Investments in Subsidiaries

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated losses under self insurance.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from inventory.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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