Segment Information - Net Sales by the Originating Geographic Area and Estimated End Market (Detail) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 27, 2015 USD ($)	Jun. 28, 2015 USD ($)	Mar. 29, 2015 USD ($)	Dec. 28, 2014 USD ($)	Sep. 28, 2014 USD ($)	Jun. 29, 2014 USD ($)	Mar. 30, 2014 USD ($)	Dec. 29, 2013 USD ($)	Sep. 27, 2015 USD ($) segment	Sep. 28, 2014 USD ($)	Sep. 29, 2013 USD ($)
Segment Reporting Disclosure [Line Items]
Number of Reportable Segments | segment									1
Net Sales	$ 328.8	$ 317.1	$ 296.2	$ 303.5	$ 303.3	$ 292.3	$ 287.0	$ 255.7	$ 1,245.6	$ 1,138.3	$ 975.9
Aerospace
Segment Reporting Disclosure [Line Items]
Net Sales									191.4	169.6	187.0
Communication
Segment Reporting Disclosure [Line Items]
Net Sales									$ 451.7	407.6	278.1
Defense And Security
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer									27.00%
Net Sales									$ 335.8	302.7	306.3
Industrial
Segment Reporting Disclosure [Line Items]
Net Sales									266.7	258.4	204.5
United States
Segment Reporting Disclosure [Line Items]
Net Sales									610.0	604.4	514.6
Europe
Segment Reporting Disclosure [Line Items]
Net Sales									$ 189.8	$ 163.7	$ 142.3
Asia
Segment Reporting Disclosure [Line Items]
Concentration of credit risk in major customer									12.00%	0.00%	0.00%
Net Sales									$ 399.7	$ 338.4	$ 292.6
Other Geographical [Member]
Segment Reporting Disclosure [Line Items]
Net Sales									$ 46.1	$ 31.8	$ 26.4