Summary of Significant Accounting Policies - Reconciliation of cash and cash equivalents and restricted cash (Table) (Details) - USD ($) $ in Thousands |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|
| Current assets: | ||||
| Cash and cash equivalents | $ 137,882 | $ 127,632 | $ 135,992 | |
| Restricted cash | 12,892 | 6,558 | 5,386 | |
| Total cash and cash equivalents and restricted cash | $ 150,774 | $ 134,190 | $ 141,378 | $ 176,892 |