Investments (Non-Cash OTTI Credit Losses Recognized in Earnings) (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
|
| Investments [Abstract] | ||||
| Balance of credit-related OTTI, beginning | $ 3,067 | $ 116 | $ 3,124 | $ 3,133 |
| Decreases for previously recognized credit-related OTTI due to transfer | 0 | 0 | 0 | (3,045) |
| Additions for decreases in cash flows expected to be collected | 0 | 0 | 0 | 33 |
| Reduction for increases in cash flows expected to be collected | (55) | (2) | (112) | (7) |
| Balance of credit-related OTTI, ending | $ 3,012 | $ 114 | $ 3,012 | $ 114 |