Long-Term Debt (Details 2) (USD $)
12 Months Ended
Dec. 31, 2014
Quarterly principal payments in fixed amounts  
2015 $ 178,116,000
2016 268,467,000
2017 294,041,000
2018 2,136,608,000
2019 20,340,000
Period of early payment of fixed principal installments of which option is available 3 months
Accumulated unrestricted cash and cash equivalents used in determining amount of additional variable payment 50,000,000
Percentage of consolidated debt used in determining amount of additional variable payment 2.00%
Percentage of relevant budget up to which operating expenses and allocated general and administrative expenses per vessel cannot exceed 20.00%
Percentage of the first specified value of net equity proceeds equal to which additional prepayments are required 50.00%
Net equity proceeds used for determining additional prepayments 300,000,000
Percentage of additional net equity proceeds equal to which additional prepayments are required to be made 25.00%
Minimum period considered for determining use of retained equity proceeds for prepayment 12 months
Voting interest owned in outstanding capital stock by Dr. Coustas and his family members, qualified for change of control (as a Percent) 33.00%
Voting interest owned by any person or group in outstanding capital stock, qualified for change of control (as a percent) 20.00%
Percentage of actual free cash flow equal to variable payment and fixed principal payment until the earlier of May 15, 2015 and the maximum consolidated net leverage ratio 92.50%
Maximum consolidated net leverage ratio 6
Percentage of actual free cash flow equal to variable payment and fixed principal payment after May 15, 2015, until maturity 89.50%
Bank agreement | January 2011 Credit Facility  
Quarterly principal payments in fixed amounts  
2015 113,358,679
2016 143,379,164
2017 148,839,796
2018 227,438,867
Total long-term debt, fixed principal repayments 633,016,506
Bank agreement | January 2011 Credit Facility | February 15  
Quarterly principal payments in fixed amounts  
2015 26,736,647
2016 30,972,971
2017 44,938,592
2018 34,152,011
Bank agreement | January 2011 Credit Facility | May 15  
Quarterly principal payments in fixed amounts  
2015 27,021,750
2016 36,278,082
2017 36,690,791
2018 37,585,306
Bank agreement | January 2011 Credit Facility | August 15  
Quarterly principal payments in fixed amounts  
2015 25,541,180
2016 32,275,598
2017 35,338,304
2018 44,398,658
Bank agreement | January 2011 Credit Facility | November 15  
Quarterly principal payments in fixed amounts  
2015 34,059,102
2016 43,852,513
2017 31,872,109
2018 45,333,618
Bank agreement | January 2011 Credit Facility | December 31  
Quarterly principal payments in fixed amounts  
2018 $ 65,969,274