Income Taxes - Schedule of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Unrecognized tax benefits-January 1, | $ 429 | $ 0 | $ 7,604 |
| Additions for: | |||
| Current year tax positions | 0 | 429 | 0 |
| Reductions for: | |||
| Settlements with tax authorities | (429) | 0 | 0 |
| Prior year tax positions | 0 | 0 | (7,604) |
| Unrecognized tax benefits-December 31, | $ 0 | $ 429 | $ 0 |