Goodwill and Intangible Assets - Additional Information (Detail) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) Reporting_Unit	Sep. 30, 2014 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2014 USD ($)
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired				$ 3,332
Goodwill		$ 3,493		3,493			$ 161
Decrease in goodwill		600
Increase (decrease) in cost of intangible assets				9,800
Amortization of intangible assets		1,125	$ 465	2,963	$ 1,503
Restructuring charges		413	$ 0	852	$ 0
RF Solutions [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill		3,493		$ 3,493
Number of reporting units for goodwill testing purposes | Reporting_Unit				2
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets basis over estimated useful lives				1 year
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets basis over estimated useful lives				8 years
Nexgen Wireless, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired				$ 3,300
Goodwill		3,332		3,332
Decrease in goodwill		600
Intangible asset		13,200		13,200
Amortization of intangible assets				3,000
Intangible asset amortization expense		700		1,700
Restructuring charges	$ 400
Envision Wireless, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired						$ 200
All Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		400		$ 1,300
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Increase (decrease) in cost of intangible assets		600
Customer Relationships [Member] | Nexgen Wireless, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Increase (decrease) in cost of intangible assets		$ 600