Discontinued Operations - Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 28, 2015	Dec. 28, 2014
Discontinued Operations and Disposal Groups [Abstract]
Cash and cash equivalents	$ 2.7	$ 1.2
Accounts receivable, net	29.8	30.7
Inventoried costs	20.1	20.6
Other current assets	1.1	1.3
Current assets of discontinued operations	53.7	53.8
Property, plant and equipment, net	20.1	21.0
Goodwill	113.0	113.0
Intangible assets, net	1.0	2.8
Other assets	0.2	0.2
Non-current assets of discontinued operations	134.3	137.0
Accounts payable	4.7	3.8
Accrued expenses	2.8	1.8
Accrued compensation	4.0	5.3
Billings in excess of cost and earnings on uncompleted contracts	3.9	2.5
Other current liabilities	0.7	1.2
Current liabilities of discontinued operations	16.1	14.6
Non-current liabilities of discontinued operations	$ 0.6	$ 0.5