Investments - Net Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
|
Investments, Debt and Equity Securities [Abstract] | ||||
Gross realized investment gains | $ 59 | $ 188 | $ 59 | $ 467 |
Gross realized investment losses | 0 | 0 | 0 | (337) |
Net realized investment gains (losses) | $ 59 | $ 188 | $ 59 | $ 130 |