Balance Sheet Components (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended			6 Months Ended					3 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 29, 2014 Minimum [Member]	Jun. 29, 2014 Maximum [Member]	Jun. 29, 2014 Retail [Member]	Jun. 29, 2014 Commercial [Member]	Jun. 29, 2014 Service Provider [Member]	Sep. 29, 2013 Sierra Wireless AirCard Business [Member]
Balance Sheet Components [Line Items]
Available-for-sale Securities, Maturity Period ( in months)						3 months	12 months
Cost method investment	$ 1,322,000		$ 1,322,000		$ 1,322,000
Cost-method Investments, Other than Temporary Impairment	0	0	0	0
Depreciation	4,200,000	4,400,000	8,500,000	7,800,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)					100,000
Amortization expense	4,400,000	5,000,000	8,900,000	6,500,000
Goodwill, Acquired During Period			0					0	0	0
Goodwill, Purchase Accounting Adjustments											500,000
Goodwill, Impairment Loss	0	0	0	0
Impairment charges											$ 2,000,000