Financial Instruments (Details 2) (USD $)
6 Months Ended 12 Months Ended
Jun. 30, 2012
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Effect of interest rate swap hedges on results        
Unrealized and realized losses on interest rate swaps   $ (98,713,000) $ (126,150,000) $ (155,173,000)
Unrealized gains/(losses)   24,915,000 22,121,000 (739,000)
Interest rate swap contracts        
Effect of interest rate swap hedges on results        
Unrealized gains/(losses) on swap asset   114,200,000 139,400,000 64,900,000
Fair Value Hedges | Interest rate swap contracts        
Fair Value Interest Rate Swap Hedges        
Fair value change of interest rate swaps   (900,000) (1,300,000) (1,100,000)
Effect of interest rate swap hedges on results        
Unrealized gains/(losses) on swap asset   (900,000) (1,300,000) (1,100,000)
Unrealized gains/(losses) on fair value of hedged debt       600,000
Amortization of fair value of hedged debt 300,000     300,000
Reclassification of fair value of hedged debt to Statement of Operations   600,000 600,000 300,000
Realized gains   1,000,000 1,400,000 1,800,000
Unrealized and realized losses on interest rate swaps   700,000 700,000 1,900,000
Related liability of fair value hedged debt     1,000,000 1,600,000
Unrealized gains/(losses) 600,000      
Fair Value Hedges | Interest rate swap contracts | Other noncurrent assets        
Effect of interest rate swap hedges on results        
Related asset of fair value hedged debt   700,000 1,600,000  
Fair Value Hedges | The Royal Bank of Scotland | Interest rate swap contracts        
Fair Value Interest Rate Swap Hedges        
Fair Value   664,000 1,586,000  
Fair Value Hedges | The Royal Bank of Scotland | Interest rate swap contracts | Effective Date 12/15/2004        
Fair Value Interest Rate Swap Hedges        
Notional Amount on Effective Date   60,528,000    
Fixed Rate (Danaos receives) (as a percent)   5.0125%    
Floating rate (Danaos pays)   USD LIBOR 3M BBA    
Margin spread on variable rate (Danaos pays) (as a percent)   0.835%    
Fair Value   302,000 747,000  
Fair Value Hedges | The Royal Bank of Scotland | Interest rate swap contracts | Effective Date 11/17/2004        
Fair Value Interest Rate Swap Hedges        
Notional Amount on Effective Date   62,342,000    
Fixed Rate (Danaos receives) (as a percent)   5.0125%    
Floating rate (Danaos pays)   USD LIBOR 3M BBA    
Margin spread on variable rate (Danaos pays) (as a percent)   0.855%    
Fair Value   $ 362,000 $ 839,000