Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.8.0.1
Debt (Details)
$ in Thousands
 8 Months Ended 9 Months Ended
Aug. 31, 2017
USD ($)
Mar. 21, 2016
USD ($)
item
Oct. 30, 2014
USD ($)
item
Aug. 31, 2017
USD ($)
Sep. 30, 2017
USD ($)
shares
Dec. 31, 2016
USD ($)
Debt disclosures            
Long-term Debt, Current Maturities           $ (400,000)
Deferred loan costs         $ (3,025) (1,488)
Total Long-term and Short-term debt         496,975 598,512
Long-term Debt         496,975 198,512
Repayments of debt         $ 600,000  
Margin Loan Agreements | Charter            
Debt disclosures            
Number of common shares pledged as collateral | shares         6,800,000  
Value of pledged collateral         $ 2,500,000  
2017 Margin Loan Agreement            
Debt disclosures            
Long-term Debt, Gross         $ 500,000  
Debt Instrument, Interest Rate, Effective Percentage         2.74%  
BroadbandSPV | Margin Loan Agreements            
Debt disclosures            
Long-term Debt, Gross $ 400,000     $ 400,000    
BroadbandSPV | Margin Loan Agreements | Three-month LIBOR            
Debt disclosures            
Interest rate basis       three-month LIBOR    
Basis spread on variable rate       1.55%    
BroadbandSPV | Margin Loan Agreements | Term loan            
Debt disclosures            
Unused commitment fee percentage       0.25%    
BroadbandSPV | Margin Loan Agreements            
Debt disclosures            
Number of debt agreements | item     2      
Maximum borrowing capacity     $ 400,000      
BroadbandSPV | 2014 Margin Loan Agreement            
Debt disclosures            
Long-term Debt, Current Maturities           (400,000)
Repayments of debt 400,000          
Cheetah 5 | Margin Loan Agreements            
Debt disclosures            
Long-term Debt, Gross           200,000
Number of debt agreements | item   2        
Maximum borrowing capacity   $ 300,000        
Cheetah 5 | Margin Loan Agreements | LIBOR            
Debt disclosures            
Interest rate basis       LIBOR    
Basis spread on variable rate       2.10%    
Cheetah 5 | Margin Loan Agreements | Term loan            
Debt disclosures            
Maximum borrowing capacity   200,000        
Cheetah 5 | Margin Loan Agreements | Draw loan            
Debt disclosures            
Maximum borrowing capacity   $ 100,000        
Unused commitment fee percentage       0.50%    
Remaining borrowing capacity 100,000     $ 100,000    
Cheetah 5 | 2016 Margin Loan Agreement            
Debt disclosures            
Long-term Debt, Gross           $ 200,000
Repayments of debt 200,000          
SPV | 2017 Margin Loan Agreement            
Debt disclosures            
Long-term Debt, Gross         $ 500,000  
Maximum borrowing capacity 1,000,000     1,000,000    
Additional allowed borrowing capacity $ 1,000,000     $ 1,000,000    
Remaining borrowing capacity         $ 500,000  
Basis spread on variable rate 0.50%          
SPV | 2017 Margin Loan Agreement | LIBOR            
Debt disclosures            
Interest rate basis LIBOR          
Basis spread on variable rate 1.00%          
SPV | 2017 Margin Loan Agreement | Three-month LIBOR            
Debt disclosures            
Interest rate basis three-month LIBOR          
Basis spread on variable rate 1.50%          
SPV | 2017 Margin Loan Agreement | Federal Funds Rate            
Debt disclosures            
Basis spread on variable rate 0.50%