Inventoried Costs (Details) (USD $) In Millions, unless otherwise specified	Sep. 28, 2014	Dec. 29, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 43.4	$ 44.5
Work in process	32.1	24.3
Finished goods	4.4	4.6
Supplies and other	2.4	1.9
Subtotal inventoried costs	82.3	75.3
Less: Customer advances and progress payments	(1.9)	(0.7)
Total inventoried costs	$ 80.4	$ 74.6