Commitments and Contingencies - Additional Information (Detail) $ in Thousands		1 Months Ended				3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 27, 2015 USD ($) ft²	Jun. 30, 2016 USD ($) ft²	Feb. 29, 2016 ft²	Oct. 31, 2015 USD ($) ft²	May 31, 2015 ft²	Jun. 30, 2016 USD ($) ft²	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) ft²	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Restructuring expenses						$ 24	$ 440	$ 541	$ 440
Restructuring reserve		$ 297				297		297		$ 237
Rent expense under leases						200	200	500	500
Operating lease obligation		3,560				3,560		3,560
Allowance for product returns								200		200
Warranty reserve		303				303		$ 303		348
Antenna [Member]
Commitments And Contingencies Disclosure [Line Items]
Repair and replacement warranty								5 years
Warranty Reserves [Member]
Commitments And Contingencies Disclosure [Line Items]
Warranty reserve		303				303	$ 304	$ 303	$ 304	348		$ 304
Melbourne, Florida [Member]
Commitments And Contingencies Disclosure [Line Items]
Area of office space before modification | ft²			6,174
Area of office space | ft²			3,600
Lease expiration date			Dec. 31, 2018
Tianjin, China [Member]
Commitments And Contingencies Disclosure [Line Items]
Area of office space | ft²				22,163
Lease expiration date				Oct. 31, 2020
Lease term				5 years
Area of office additional manufacturing space | ft²				44,289
Operating lease obligation				$ 200
Englewood, Colorado [Member]
Commitments And Contingencies Disclosure [Line Items]
Area of office space | ft²					4,759
Lease expiration date					Oct. 31, 2020
Lease term					5 years 5 months
Operating lease obligation		$ 500				$ 500		$ 500
Schaumburg, Illinois [Member]
Commitments And Contingencies Disclosure [Line Items]
Area of office space | ft²	6,652
Lease expiration date	Oct. 31, 2018
Operating lease obligation	$ 300
Lease option on early termination date	Aug. 31, 2016
Termination fee on early payment											$ 57
Beijing Design Center [Member]
Commitments And Contingencies Disclosure [Line Items]
Area of office space | ft²		5,393				5,393		5,393
Lease term		4 years
Operating lease obligation		$ 400				$ 400		$ 400
Accrued liabilities
Commitments And Contingencies Disclosure [Line Items]
Restructuring reserve		200				200		200
Long-term liabilities
Commitments And Contingencies Disclosure [Line Items]
Restructuring reserve		100				100		100
Employee Severance and Related Costs [Member]
Commitments And Contingencies Disclosure [Line Items]
Restructuring expenses								200
Lease Terminations [Member]
Commitments And Contingencies Disclosure [Line Items]
Restructuring expenses								239
Restructuring reserve		155				155		155		0
Disposal of Fixed Assets [Member]
Commitments And Contingencies Disclosure [Line Items]
Restructuring expenses								49
Restructuring reserve		$ 0				$ 0		$ 0		$ 0