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Long-Term Debt - Credit Facilities And Senior Notes (Details) - USD ($) $ in Thousands | 5 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
May 18, 2017 | Jun. 23, 2014 | Jun. 19, 2014 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 17, 2015 | Sep. 15, 2014
Debt Instruments |  |  |  |  |  |  |  |
Weighted average interest rate |  |  |  | 5.40% | 4.40% | 4.50% |  |
Total interest incurred on long-term debt |  |  |  | $ 39,775 | $ 32,887 | $ 25,926 |  |
Debt instrument, remaining borrowing capacity |  |  |  | 0 | 0 |  |  |
Line of credit facility, commitment fee amount |  |  |  | 0 | 2 | 15 |  |
Decrease/ (Increase) in restricted cash |  |  |  | $ 25,000 | $ 0 | (1,000) |  |
$250.0 Million Senior Unsecured Notes due 2019 |  |  |  |  |  |  |  |
Debt Instruments |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  |  |  | $ 250,000
Debt Instrument, Maturity Date |  |  |  | Oct. 30, 2019 |  |  |  |
Senior notes, terms |  |  |  | The Notes bear interest from the date of the original issue until maturity at a rate of 6.25% per year, payable quarterly in arrears on January 30, April 30, July 30 and October 30 of each year. |  |  |  |
Senior notes interest rate |  |  |  | 6.25% |  |  |  |
$340 million Credit Suisse Senior Secured Revolving Credit Facility |  |  |  |  |  |  |  |
Debt Instruments |  |  |  |  |  |  |  |
Principal amount |  |  | $ 340,000 |  |  |  |  |
Amount repaid |  | $ 214,100 |  |  |  |  |  |
Debt instrument, description of variable rate basis |  |  | LIBOR |  |  |  |  |
Decrease/ (Increase) in restricted cash | $ 25,000 |  |  |  |  |  |  |
$200 Million Term Loan Facility |  |  |  |  |  |  |  |
Debt Instruments |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  |  | $ 200,000 |
Debt instrument, description of variable rate basis |  |  |  |  |  |  | LIBOR |
Debt instrument, remaining borrowing capacity |  |  |  |  |  | $ 66,700 |  |
$480 Term Loan B |  |  |  |  |  |  |  |
Debt Instruments |  |  |  |  |  |  |  |
Principal amount | $ 480,000 |  |  |  |  |  |  |
Line of credit facility, frequency of payments |  |  |  | quarterly |  |  |  |
Debt Instrument, Maturity Date |  |  |  | May 18, 2023 |  |  |  |
Debt instrument, description of variable rate basis | LIBOR |  |  |  |  |  |  |
Debt instrument, payment percentage |  |  |  | 0.25% |  |  |  |

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