Investments in Available-For-Sale Securities (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Schedule Of Equity Method Investments [Line Items] | |||
| Reclassification to earnings | $ 345 | $ 1,782 | $ 11,553 |
| Investment in available-for-sale-securities | $ 0 | 5,173 | |
| Accumulated other comprehensive loss | $ (445) | ||
| KLC and STX | |||
| Schedule Of Equity Method Investments [Line Items] | |||
| Investment held in shares | 0 | 344,649 | |
| Available for sale securities | 354,093 | ||
| Consideration received for AFS securities sold | $ 5,303 | ||
| Investment in available-for-sale-securities | 0 | $ 5,173 | |
| Korea Line Corporation (''KLC'') | |||
| Schedule Of Equity Method Investments [Line Items] | |||
| Reclassification to earnings | $ (345) | $ (1,783) | $ (11,553) |