Restructuring - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 Employees	Dec. 31, 2012	Dec. 31, 2011
Restructuring Cost and Reserve [Line Items]
Reduction in number of employees after restructuring		72
Restructuring charges	$ 893,000	$ 3,304,000	$ 0	$ 0
Accrued liabilities relating to restructuring	881,000	881,000	0
Deferred rent included in accrued liabilities relating restructuring	424,000	424,000
Restructuring Accruals		3,728,000
Short-term [Member]
Restructuring Cost and Reserve [Line Items]
Accrued liabilities relating to restructuring	610,000	610,000
Long-term [Member]
Restructuring Cost and Reserve [Line Items]
Accrued liabilities relating to restructuring	271,000	271,000
Mobile Computing Products [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		3,100,000
M2M Products and Solutions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		206,000
Employee Severance Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		2,300,000
Accrued liabilities relating to restructuring	0	0	0
Restructuring Accruals		2,273,000
Facility Exit Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		1,000,000
Other Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Accrued liabilities relating to restructuring	881,000	881,000	0
Restructuring Accruals		1,455,000
Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Fixed asset impairments charges	$ 348,000