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) - USD ($)
 3 Months Ended 12 Months Ended
Mar. 27, 2018
Mar. 31, 2018
Dec. 31, 2017
Mar. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Jul. 27, 2016
Feb. 28, 2015
Accounting Policies [Line Items]                
Adoption of ASC 606 - Cumulative Adjustment     $ 933,000   $ 933,000      
Stated interest rate               2.75%
Decrease in revenue   $ (156,497,000)   $ (152,592,000)        
Decrease in cost of goods sold   (118,496,000)   (110,540,000)        
Cash and cash equivalents   168,931,000 48,260,000   48,260,000      
Proceeds from Issuance of Debt $ 143,000,000              
Restricted Cash                
Restricted cash   3,388,000 3,608,000   3,608,000      
Intangible Assets and Goodwill:                
Impairment of goodwill   0   78,000,000 167,000,000      
Goodwill   159,654,000 159,696,000   159,696,000      
Income Taxes                
Income tax benefit due to the Tax Act         4,600,000      
Impact due to repatriation charge         0      
Repatriation charge         18,500,000      
Adoption of New Accounting Standards                
Increase in cash equivalents and restricted cash balances [1]   172,319,000 51,868,000 123,488,000 51,868,000 $ 68,678,000    
Decrease in cash used by operating activities   3,953,000   35,374,000        
Media & Content                
Intangible Assets and Goodwill:                
Impairment of goodwill   0            
Goodwill   83,503,000 83,529,000   83,529,000      
Maritime & Land Connectivity Reporting Unit                
Intangible Assets and Goodwill:                
Impairment of goodwill   0 45,000,000 78,000,000        
Goodwill   22,130,000 22,130,000   22,130,000      
Wireless Maritime Services                
Investments in Equity Affiliates                
Equity method investment, ownership percentage             49.00%  
Santander                
Investments in Equity Affiliates                
Equity method investment, ownership percentage             49.00%  
Accumulated Deficit                
Accounting Policies [Line Items]                
Adoption of ASC 606 - Cumulative Adjustment     933,000   933,000      
Additional Paid-in Capital                
Accounting Policies [Line Items]                
Adoption of ASC 606 - Cumulative Adjustment     0   0      
MTN                
Restricted Cash                
Restricted cash           16,000,000    
Public SPAC Warrants                
Derivative Warrants                
Change in value   100,000   400,000        
ASU 2014-09 | Accumulated Deficit                
Accounting Policies [Line Items]                
Adoption of ASC 606 - Cumulative Adjustment     $ 900,000   $ 900,000      
Decrease in revenue   700,000            
Decrease in cost of goods sold   $ 400,000            
Adoption of New Accounting Standards                
Increase in cash equivalents and restricted cash balances       18,100,000   $ 18,000,000    
Decrease in cash used by operating activities       $ 100,000        
[1] March 31, 2017 figures have been recast to include the impact of the adoption of ASU 2016-18. See Note 2. Basis of Presentation and Summary of Significant Accounting Policies