Severance, impairment and other associated costs (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012
Restructuring Reserve [Roll Forward]
Balance accrued at beginning of period	$ 0.7
Net expense	2.8
Cash payments	(1.2)
Non-cash charges	(1.3)
Balance accrued at end of period	1.0
Restructuring and impairment charges	2.8	5.9
Severance and related costs	1.2
Workforce reduction		1.1
Accrual for restructuring actions	1.0
Chinese Manufacturing plants [Member]
Restructuring Reserve [Roll Forward]
Severance and related costs	0.7	3.7
Korean Manufacturing Plant [Member]
Restructuring Reserve [Roll Forward]
Severance and related costs		0.2
Impairment of fixed assets		0.7
Network [Member]
Restructuring Reserve [Roll Forward]
Impairment of fixed assets	1.6
Wireless [Member]
Restructuring Reserve [Roll Forward]
Severance and related costs	0.5
Other restructuring costs		$ 0.2