Reinsurance - Summary of Reinsurance Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Gross Amount
Premiums written and contract deposits, Gross Amount	$ 322,428	$ 356,155	$ 940,063	$ 960,945
Premiums and contract charges earned, Gross Amount	202,988	195,654	603,794	579,283
Benefits, claims and settlement expenses, Gross Amount	135,508	139,114	450,997	422,352
Ceded to Other Companies
Premiums written and contract deposits, Ceded to Other Companies	5,189	5,555	16,342	17,244
Premiums and contract charges earned, Ceded to Other Companies	5,216	5,584	16,415	17,305
Benefits, claims and settlement expenses, Ceded to Other Companies	1,831	4,642	8,899	21,748
Assumed from Other Companies
Premiums written and contract deposits, Assumed from Other Companies	1,116	934	2,980	2,881
Premiums and contract charges earned, Assumed from Other Companies	1,163	980	2,996	2,882
Benefits, claims and settlement expenses, Assumed from Other Companies	1,218	1,238	2,772	3,027
Net Amount
Premiums written and contract deposits, Net Amount	318,355	351,534	926,701	946,582
Premiums and contract charges earned, Net Amount	198,935	191,050	590,375	564,860
Benefits, claims and settlement expenses, Net Amount	$ 134,895	$ 135,710	$ 444,870	$ 403,631