Acquisitions - Summary of Useful Lives of Customer Relationships Based on Customer Attrition (Detail) - Jun. 30, 2015 - USD ($) $ in Thousands	Total
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	10 years 3 months 18 days
Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	10 years 6 months
SkyWave Mobile Communications Inc. [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total intangible assets	$ 67,214
SkyWave Mobile Communications Inc. [Member] | Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	10 years
Total intangible assets	$ 59,371
SkyWave Mobile Communications Inc. [Member] | IDP Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	10 years
Total intangible assets	$ 5,463
SkyWave Mobile Communications Inc. [Member] | M2M and DGS Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	5 years
Total intangible assets	$ 1,318
SkyWave Mobile Communications Inc. [Member] | Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	5 years
Total intangible assets	$ 1,062
Insync, Inc [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total intangible assets	$ 5,788
Insync, Inc [Member] | Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	14 years
Total intangible assets	$ 5,056
Insync, Inc [Member] | IDP Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	10 years
Total intangible assets	$ 632
Insync, Inc [Member] | Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful life (in years)	4 years
Total intangible assets	$ 100