Investments - Net Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Gross realized investment gains | $ 66 | $ 266 | $ 683 | $ 1,526 |
| Gross realized investment losses | 0 | (281) | (1,441) | (574) |
| Net realized investment gains (losses) | $ 66 | $ (15) | $ (758) | $ 952 |