Segment Information and Concentrations of Risk - Schedule of Net Revenues, Operating Income (Loss) and Identifiable Assets of Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net revenues by reportable segment:
Net revenues	$ 55,361	$ 44,330	$ 37,270	$ 48,284	$ 65,335	$ 92,673	$ 91,124	$ 85,921	$ 185,245	$ 335,053	$ 344,288
Operating income (loss):
Operating loss:									(35,573)	(43,221)	(88,743)
Identifiable assets by reportable segment:
Identifiable assets by reportable segment:	95,020				111,465				95,020	111,465
Mobile Computing Products
Net revenues by reportable segment:
Net revenues									145,500	297,499	312,508
Operating income (loss):
Operating loss:									(23,339)	(27,939)	(22,924)
Identifiable assets by reportable segment:
Identifiable assets by reportable segment:	79,368				96,516				79,368	96,516
M2M Products and Solutions
Net revenues by reportable segment:
Net revenues									39,745	37,554	31,780
Operating income (loss):
Operating loss:									(12,234)	(15,282)	(65,819)
Identifiable assets by reportable segment:
Identifiable assets by reportable segment:	$ 15,652				$ 14,949				$ 15,652	$ 14,949