Summary of Significant Accounting Policies - Additional Information (Detail)		1 Months Ended	3 Months Ended			12 Months Ended
	Sep. 15, 2014 USD ($)	Jan. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2014 Satellite	Dec. 31, 2015 USD ($) Satellite Customer Segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Equity method investments			$ 0			$ 0	$ 0
Guarantee or other funding obligations under equity method investment			0			0	0	$ 0
Losses from equity method investment						0	0	0
Acquisition-related and integration costs						$ 4,803,000	3,819,000	1,658,000
Warranty period						1 year
Estimated life of communicator						5 years
Number of assets operated communications and broadcasting equipment | Satellite						41
Number of satellite networks buying network connectivity | Customer						2
Number of terrestrial network partners buying network connectivity | Customer						7
Foreign currency translation gain (loss)						$ 413,000	207,000	(32,000)
Cash and cash equivalents			27,077,000			27,077,000	91,565,000	68,354,000	$ 34,783,000
Cash held for acquisition							123,000,000
Amount used to fund the acquisition						$ 123,000,000	(123,000,000)
Accounts receivable due from contract manufacturers							1,289,000
Number of customers with revenues greater than 10% | Customer						0
Inventories finished goods and purchased parts			16,912,000			$ 16,912,000
Inventories raw materials			3,800,000			3,800,000
Interest capitalized						4,688,000	4,713,000	4,562,000
Impairment charges - satellite network				$ 12,748,000		$ 12,748,000	605,000
Number of reporting segments | Segment						1
Goodwill impairment charges						$ 0	$ 0	$ 0
Impairment charge of intangible assets			$ 564,000
Maximum percentage of benefit realized upon ultimate settlement						50.00%
Sales [Member] | Customer Concentration Risk [Member] | Caterpillar Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Customers with revenues greater than 10%							12.40%	17.30%
Sales [Member] | Customer Concentration Risk [Member] | Komatsu Ltd. [Member]
Summary Of Significant Accounting Policies [Line Items]
Customers with revenues greater than 10%							10.60%	12.10%
SkyWave Mobile Communications Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Amount used to fund the acquisition		$ 122,500,000
Working capital adjustments						$ 500,000
Gateway Earth Stations [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of assets operated communications and broadcasting equipment | Satellite						15
AIS Data Reception Earth Stations [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of assets operated communications and broadcasting equipment | Satellite						3
Regional Gateway Control Centers [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of assets operated communications and broadcasting equipment | Satellite						3
Next-generation OG2 Satellites [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of satellites placed in service | Satellite					6
Reclassification of costs out of assets under construction into satellite network	$ 82,725,000
Satellites, life in years	10 years					10 years
Depreciation						$ 6,957,000	$ 2,431,000
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Additional term of the agreement						2 years
Amortization of internal use software costs, useful life						3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Additional term of the agreement						5 years
Amortization of internal use software costs, useful life						7 years