Discontinued Operations - Assets and Liabilities (Details) - USD ($) $ in Millions	Apr. 01, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets of discontinued operations	$ 52.1	$ 58.6
Non-current assets of discontinued operations	38.8	38.8
Current liabilities of discontinued operations	23.2	29.2
Non-current liabilities of discontinued operations	5.9	6.0
Herley | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	(0.7)	(0.9)
Accounts receivable, net and unbilled receivables, net	48.6	56.0
Inventoried costs	2.6	1.5
Other current assets	1.6	2.0
Current assets of discontinued operations	52.1	58.6
Property, plant and equipment, net	3.0	3.0
Goodwill	35.6	35.6
Other assets	0.2	0.2
Non-current assets of discontinued operations	38.8	38.8
Accounts payable	9.4	14.2
Accrued expenses	3.4	4.7
Accrued compensation	4.9	4.6
Billings in excess of cost and earnings on uncompleted contracts	4.5	4.3
Other current liabilities	1.0	1.4
Current liabilities of discontinued operations	23.2	29.2
Non-current liabilities of discontinued operations	$ 5.9	$ 6.0