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