Income Taxes (Deferred Income Tax Assets and Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 26, 2014	Dec. 27, 2013
Current:
Allowances and other accrued liabilities	$ (2.7)	$ (1.3)
Inventories	(15.6)	(14.4)
Total current tax liabilities	(18.3)	(15.7)
Noncurrent:
Property, plant and equipment	(64.7)	(68.1)
Equity in earnings of unconsolidated companies	(0.2)	(0.2)
Deferred Tax Liabilities, Other Comprehensive Income	(2.8)	(3.6)
Other noncurrent liabilities	(6.3)	(7.3)
Total noncurrent deferred tax liabilities	(74.0)	(79.2)
Total current and noncurrent deferred tax liabilities	(92.3)	(94.9)
Current:
Net operating loss carryforwards	6.4	3.1
Allowances and other accrued assets	13.2	13.0
Inventories	4.8	3.7
Total current deferred tax assets	24.4	19.8
Valuation allowance	(12.1)	(9.0)
Total net current deferred tax assets	12.3	10.8
Noncurrent:
Pension liability	22.1	20.2
Property, plant and equipment	2.4	4.0
Post-retirement benefits other than pension	0.3	0.5
Net operating loss carryforwards	158.8	162.9
Capital loss carryover	3.5	3.1
Other noncurrent assets	26.1	33.1
Total noncurrent deferred tax assets	213.2	223.8
Valuation allowance	(167.4)	(171.4)
Total net noncurrent deferred tax assets	45.8	52.4
Total deferred tax assets, net	58.1	63.2
Net deferred tax liabilities	$ (34.2)	$ (31.7)