Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|---|
| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Beginning and end of year balance | $ 1,900 | $ 1,900 | $ 1,900 |