Investments Cash, Cash Equivalent and Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Fixed maturity securities	$ 1,208,570	$ 1,128,672
Fixed maturity securities percent	89.30%	89.70%
Equity securities	$ 16,164	$ 18,159
Equity securities percent	1.20%	1.60%
Mortgage loans	$ 195	$ 232
Mortgage loans percent	0.00%	0.00%
Policy loans	$ 73,735	$ 66,672
Policy loans percent	5.50%	5.30%
Real estate and other long-term investments	$ 7,452	$ 7,896
Real estate and other long-term investments percent	0.60%	0.60%
Short-term investments	$ 0	$ 508
Short-term investment percentage	0.00%	0.00%
Cash and cash equivalents	$ 46,064	$ 35,510	$ 82,827	$ 50,708
Cash and cash equivalents percent	3.40%	2.80%
Total cash, cash equivalents and investments	$ 1,352,180	$ 1,257,649
Total cash, cash equivalents and investments percent	100.00%	100.00%
Percent of high quality fixed maturity securities	75.20%