Reinsurance - Summary of Reinsurance Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Gross Amount
Premiums written and contract deposits, Gross Amount	$ 299,093	$ 288,816
Premiums and contract charges earned, Gross Amount	213,256	207,737
Benefits, claims and settlement expenses, Gross Amount	142,052	151,968
Ceded to Other Companies
Premiums written and contract deposits, Ceded to Other Companies	5,848	5,514
Premiums and contract charges earned, Ceded to Other Companies	5,822	5,528
Benefits, claims and settlement expenses, Ceded to Other Companies	4,292	9,014
Assumed from Other Companies
Premiums written and contract deposits, Assumed from Other Companies	2,149	706
Premiums and contract charges earned, Assumed from Other Companies	2,351	789
Benefits, claims and settlement expenses, Assumed from Other Companies	1,624	608
Net Amount
Premiums written and contract deposits, Net Amount	295,394	284,008
Premiums and contract charges earned, Net Amount	209,785	202,998
Benefits, claims and settlement expenses, Net Amount	$ 139,384	$ 143,562