Contingencies - Additional Information (Detail) $ in Millions			6 Months Ended
	Jun. 01, 2014 USD ($)	Mar. 25, 2014 USD ($)	Jul. 04, 2015 USD ($) Manufacturers_Distributors Complaints Defendant	Dec. 31, 2014 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Accrual for environmental loss contingencies, gross			$ 22.0	$ 27.2
Accrued environmental loss contingencies, current			10.6	11.3
Accrued environmental loss contingencies, noncurrent			$ 11.4	$ 15.9
Steel manufacturers, number of manufacturers | Manufacturers_Distributors			8
Additional complaints being filed in July and December of 2010 | Complaints			2
Complaints that are dismissed | Complaints			2
Defendants that have reached court approved settlements with the plaintiffs | Defendant			5
Damages against all defendants jointly and severally	$ 160.8	$ 52.0
Practical estimable exposure			$ 40.0