Acquisitions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended			0 Months Ended	3 Months Ended	9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013	Dec. 29, 2013	Jan. 21, 2014 Xsens Holdings BV	Sep. 28, 2014 Xsens Holdings BV	Sep. 28, 2014 Xsens Holdings BV	Jan. 21, 2014 Xsens Holdings BV
Business Acquisition [Line Items]
Business acquisition, cash payment						$ 57.8
Acquisitions, net of cash acquired			56.6			56.6
Cash acquired from acquisition						1.2
Amortization of acquisition-related intangibles	2.1	3.9	8.5	11.6			0.8	2.3
Goodwill	$ 211.3		$ 211.3		$ 169.3		$ 44.4	$ 44.4	$ 44.4