Discontinued Operations - Results of Discontinued Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on disposal of discontinued operations before income taxes			$ 0.0
Total gain (loss) of discontinued operations before income taxes	$ (1.2)	$ 1.9	(9.4)
Income tax expense (benefit)	(0.3)	0.2	(1.8)
Income (loss) from discontinued operations	(0.9)	1.7	(7.6)
Herley | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0.0	0.3	44.2
Cost of sales	0.2	0.9	34.2
Selling, general and administrative expenses	1.0	1.1	16.7
Other (income) expense	0.0	(3.6)	2.7
Income (loss) from discontinued operations before income taxes	(1.2)	1.9	(9.4)
Gain on disposal of discontinued operations before income taxes	0.0	0.0	0.0
Total gain (loss) of discontinued operations before income taxes	(1.2)	1.9	(9.4)
Income tax expense (benefit)	(0.3)	0.2	(1.8)
Income (loss) from discontinued operations	$ (0.9)	$ 1.7	$ (7.6)