Investments (Details 3) $ in Thousands	Mar. 31, 2016 USD ($) Holdings	Dec. 31, 2015 USD ($) Holdings
Fair value
Less than 12 months	$ 134,530	$ 244,279
12 months or longer	67,775	48,518
Total	202,305	292,797
Unrealized losses
Less than 12 months	1,758	2,882
12 months or longer	2,127	3,151
Total	$ 3,885	$ 6,033
No. of holdings | Holdings	305	407
Investment grade
Fair value
Less than 12 months	$ 92,506	$ 174,723
12 months or longer	46,471	38,369
Total	138,977	213,092
Unrealized losses
Less than 12 months	556	1,296
12 months or longer	1,423	1,256
Total	$ 1,979	$ 2,552
No. of holdings | Holdings	76	105
Non-investment grade
Fair value
Less than 12 months	$ 42,024	$ 56,824
12 months or longer	12,372	10,149
Total	54,396	66,973
Unrealized losses
Less than 12 months	1,202	1,453
12 months or longer	688	1,895
Total	$ 1,890	$ 3,348
No. of holdings | Holdings	228	301
Fixed maturities
Fair value
Less than 12 months	$ 134,530	$ 231,547
12 months or longer	58,843	48,518
Total	193,373	280,065
Unrealized losses
Less than 12 months	1,758	2,749
12 months or longer	2,111	3,151
Total	$ 3,869	$ 5,900
No. of holdings | Holdings	304	406
States & political subdivisions
Fair value
Less than 12 months	$ 6,938	$ 5,867
12 months or longer	0	0
Total	6,938	5,867
Unrealized losses
Less than 12 months	7	7
12 months or longer	0	0
Total	$ 7	$ 7
No. of holdings | Holdings	3	3
Corporate debt securities
Fair value
Less than 12 months	$ 83,699	$ 172,831
12 months or longer	30,239	19,086
Total	113,938	191,917
Unrealized losses
Less than 12 months	1,331	2,447
12 months or longer	793	1,965
Total	$ 2,124	$ 4,412
No. of holdings | Holdings	251	349
Residential mortgage-backed securities
Fair value
Less than 12 months	$ 5,333	$ 9,827
12 months or longer	2,886	936
Total	8,219	10,763
Unrealized losses
Less than 12 months	12	84
12 months or longer	114	46
Total	$ 126	$ 130
No. of holdings | Holdings	7	9
Commercial mortgage-backed securities
Fair value
Less than 12 months	$ 9,321	$ 13,081
12 months or longer	17,371	19,081
Total	26,692	32,162
Unrealized losses
Less than 12 months	77	68
12 months or longer	1,071	1,021
Total	$ 1,148	$ 1,089
No. of holdings | Holdings	22	24
Collateralized debt obligations
Fair value
Less than 12 months	$ 27,289	$ 27,981
12 months or longer	8,279	9,174
Total	35,568	37,155
Unrealized losses
Less than 12 months	281	103
12 months or longer	133	118
Total	$ 414	$ 221
No. of holdings | Holdings	19	19
Other debt securities
Fair value
Less than 12 months	$ 1,950	$ 1,960
12 months or longer	68	241
Total	2,018	2,201
Unrealized losses
Less than 12 months	50	40
12 months or longer	0	1
Total	$ 50	$ 41
No. of holdings | Holdings	2	2
Common stock
Fair value
Less than 12 months	$ 0	$ 12,732
12 months or longer	8,932	0
Total	8,932	12,732
Unrealized losses
Less than 12 months	0	133
12 months or longer	16	0
Total	$ 16	$ 133
No. of holdings | Holdings	1	1