Commitments and Contingencies (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Apr. 30, 2016 USD ($)	Mar. 27, 2016 USD ($)	Sep. 25, 2016 USD ($)	Sep. 27, 2015 USD ($)	Jul. 28, 2015 subsidiary
Commitments and Contingencies Disclosure [Abstract]
Number of subsidiaries with certain unallowable costs | subsidiary					1
Loss Contingencies [Line Items]
Litigation related charges			$ 1.7	$ 0.0
Settled Litigation
Loss Contingencies [Line Items]
Settlement amount related to unallowable costs	$ 0.2
Settled Litigation | Public Safety & Security
Loss Contingencies [Line Items]
Litigation related charges		$ 1.9	$ 1.9