Other Investments - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014 Agreement	Jun. 30, 2013	Dec. 31, 2013
Variable Interest Entity [Line Items]
Ownership interest in investment	27.00%		27.00%
Number of supply agreements with GWS	2
Purchase of components under agreement	$ 1,496,000	$ 433,000
Company owed GWS	166,000		152,000
Great Wall Semiconductor Corporation (GWS) [Member]
Variable Interest Entity [Line Items]
Investment in non-voting convertible preferred stock	0		0
Great Wall Semiconductor Corporation (GWS) [Member] | Convertible Preferred Stock [Member]
Variable Interest Entity [Line Items]
Investment in non-voting convertible preferred stock	$ 5,000,000		$ 5,000,000