Restructuring and Divestiture Charges - Charges Taken Related to Restructuring Actions (Detail) - USD ($) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Jun. 25, 2016	Jul. 01, 2017	Jun. 25, 2016	Sep. 24, 2016
Bedford [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 0.0			$ (0.5)		$ (1.4)	$ (1.7)
Facility Closure Costs	1.3		$ 3.5
Cynosure
Restructuring Cost and Reserve [Line Items]
Severance Costs	(4.3)	$ (1.5)
Restructuring | Two Thousand Sixteen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve							6.3
Restructuring | Year Two Thousand Sixteen [Domain]
Restructuring Cost and Reserve [Line Items]
Reduction Of Workforce Expenses							10.5
Fiscal restructuring charges							10.5
Restructuring | Two Thousand Seventeen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	10.8				$ 10.8
Severance Costs					6.0
Facility Closure Costs					4.8
Fiscal restructuring charges					10.8
Restructuring | Fiscal 2017 Actions [Member] | Two Thousand Sixteen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve							0.0
Restructuring | Fiscal 2017 Actions [Member] | Year Two Thousand Sixteen [Domain]
Restructuring Cost and Reserve [Line Items]
Reduction Of Workforce Expenses							0.0
Fiscal restructuring charges							0.0
Restructuring | Fiscal 2017 Actions [Member] | Two Thousand Seventeen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	5.8				5.8
Severance Costs					5.8
Facility Closure Costs					0.0
Fiscal restructuring charges					5.8
Restructuring | Fiscal 2016 Actions [Domain] | Two Thousand Sixteen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve							5.5
Restructuring | Fiscal 2016 Actions [Domain] | Year Two Thousand Sixteen [Domain]
Restructuring Cost and Reserve [Line Items]
Reduction Of Workforce Expenses							10.5
Fiscal restructuring charges							10.5
Restructuring | Fiscal 2016 Actions [Domain] | Two Thousand Seventeen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	4.6				4.6
Severance Costs					0.2
Facility Closure Costs					4.8
Fiscal restructuring charges					5.0
Restructuring | Fiscal 2015 Actions | Two Thousand Sixteen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve							0.2
Restructuring | Fiscal 2015 Actions | Two Thousand Seventeen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0.0				0.0
Restructuring | Fiscal 2014 Actions | Two Thousand Sixteen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve							$ 0.6
Restructuring | Fiscal 2014 Actions | Two Thousand Seventeen [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0.4				$ 0.4