Reinsurance and Catastrophes (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Effects of reinsurance on premiums and benefits
Premiums written and contract deposits, Gross Amount	$ 1,280,903	$ 1,277,066	$ 1,191,123
Premiums written and contract deposits, Ceded to Other Companies	22,728	24,737	27,144
Premiums written and contract deposits, Assumed from Other Companies	4,324	4,184	3,676
Premiums written and contract deposits, Net Amount	1,262,499	1,256,513	1,167,655
Premiums and contract charges earned, Gross Amount	777,651	752,798	739,281
Premiums and contract charges earned, Ceded to Other Companies	22,826	25,077	27,276
Premiums and contract charges earned, Assumed from Other Companies	4,321	4,159	3,755
Premiums and contract charges earned, Net Amount	759,146	731,880	715,760
Benefits, claims and settlement expenses, Gross Amount	562,385	508,904	504,550
Benefits, claims and settlement expenses, Ceded to Other Companies	25,739	16,221	39,236
Benefits, claims and settlement expenses, Assumed from Other Companies	4,358	3,681	3,112
Benefits, claims and settlement expenses, Net Amount	$ 541,004	$ 496,364	$ 468,426