Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)

v3.8.0.1
Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Dec. 31, 2017
USD ($)
Jun. 30, 2017
USD ($)
Mar. 31, 2017
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
Jun. 30, 2016
USD ($)
Dec. 31, 2016
USD ($)
Jul. 27, 2016
member
Dec. 31, 2015
USD ($)
Accounting Policies [Line Items]                  
Cash and cash equivalents   $ 66,554   $ 196,709 $ 66,554 $ 196,709 $ 50,686   $ 223,552
Restricted Cash                  
Restricted cash   1,021     1,021   17,992    
Release of restricted cash         17,100        
Intangible Assets and Goodwill:                  
Impairment of goodwill   0   $ 0 78,000 0      
Goodwill   248,644     248,644   327,836    
Investments in Equity Affiliates                  
Board of directors members, voting | member               2  
Board of directors members | member               2  
Derivative Warrants                  
Change in fair value         $ 2,475 $ 16,792      
Change in accounting principle [1]             0    
Buildings                  
Property, plant and equipment                  
Property, plant and equipment, useful life         30 years        
Connectivity equipment                  
Property, plant and equipment                  
Property, plant and equipment, useful life         5 years        
Minimum | Equipment                  
Property, plant and equipment                  
Property, plant and equipment, useful life         3 years        
Maximum                  
Restricted Cash                  
Restricted cash, maximum term of restriction         3 years        
Maximum | Equipment                  
Property, plant and equipment                  
Property, plant and equipment, useful life         10 years        
Media & Content                  
Intangible Assets and Goodwill:                  
Impairment of goodwill         $ 0        
Goodwill   83,477     $ 83,477   83,419    
Connectivity | Minimum | Equipment                  
Property, plant and equipment                  
Property, plant and equipment, useful life         7 years        
Connectivity | Maximum | Equipment                  
Property, plant and equipment                  
Property, plant and equipment, useful life         15 years        
Maritime & Land Connectivity                  
Intangible Assets and Goodwill:                  
Impairment of goodwill     $ 78,000   $ 78,000   64,000    
Goodwill   67,130     67,130   146,380    
Wireless Maritime Services                  
Investments in Equity Affiliates                  
Ownership percentage               49.00%  
Board of directors members, voting | member               5  
Santander                  
Investments in Equity Affiliates                  
Ownership percentage               49.00%  
Board of directors members, voting | member               5  
AT&T | Wireless Maritime Services                  
Investments in Equity Affiliates                  
Ownership percentage               51.00%  
Board of directors members, voting | member               3  
Erzia | Santander                  
Investments in Equity Affiliates                  
Ownership percentage               51.00%  
Board of directors members | member               3  
Additional Paid-in Capital                  
Derivative Warrants                  
Change in accounting principle [1]             $ 288    
MTN                  
Restricted Cash                  
Release of restricted cash         16,000        
MTN | Former Stockholders of Maritime Telecommunications Network                  
Restricted Cash                  
Release of restricted cash         15,500        
MTN | Global Eagle Entertainment Inc.                  
Restricted Cash                  
Release of restricted cash         600        
Letters of Credit                  
Restricted Cash                  
Release of restricted cash         1,100        
Subsequent Event                  
Accounting Policies [Line Items]                  
Cash and cash equivalents $ 50,800                
Public SPAC Warrants                  
Derivative Warrants                  
Change in fair value   $ (200)     $ 200        
Forecast | Minimum                  
Income Tax Expense (Benefit), Continuing Operations [Abstract]                  
Income tax benefit expected due to change in tax law 5,000                
Forecast | Maximum                  
Income Tax Expense (Benefit), Continuing Operations [Abstract]                  
Income tax benefit expected due to change in tax law $ 8,000                
[1] Cumulative-effect adjustment related to the adoption of ASU 2016-09, as defined in Note 2. Basis of Presentation and Summary of Significant Accounting Policies.