Income Taxes - Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 27, 2019	Dec. 28, 2018
Deferred tax liabilities:
Allowances and other accrued liabilities	$ (1.5)	$ 0.0
Inventories	(16.3)	(13.7)
Property, plant and equipment	(70.6)	(70.2)
Equity in earnings of unconsolidated companies	(0.1)	(0.1)
Pension obligations	(3.1)	(2.5)
Other noncurrent deferred tax liabilities	(12.3)	(6.5)
ROU Assets	(25.6)
Total noncurrent deferred tax liabilities	(129.5)	(93.0)
Deferred tax assets:
Allowances and other accrued assets	13.5	10.6
Inventories	5.5	5.6
Pension obligations	27.7	24.8
Property, plant and equipment	2.1	2.3
Post-retirement benefits other than pension	1.0	1.0
Net operating loss carryforwards	318.0	287.1
Capital loss carryover	1.5	1.6
Other noncurrent assets	28.5	26.9
Operating Lease	25.8
Total noncurrent deferred tax assets	423.6	359.9
Valuation allowance	(323.3)	(291.8)
Total deferred tax assets, net	100.3	68.1
Net deferred tax liabilities	$ (29.2)	$ (24.9)