Discontinued Operations - Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets of discontinued operations	$ 5.3	$ 8.3
Current liabilities of discontinued operations	3.5	5.3
Long-term liabilities of discontinued operations	2.8	6.4
Herley | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable, net and unbilled receivables, net	5.2	8.2
Other current assets	0.1	0.1
Current assets of discontinued operations	5.3	8.3
Accounts payable	0.3	0.3
Accrued expenses	0.2	0.4
Other current liabilities	3.0	4.6
Current liabilities of discontinued operations	3.5	5.3
Long-term liabilities of discontinued operations	$ 2.8	$ 6.4