Investments Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Marketable Securities
Estimated Fair Value, Less than 12 Months	$ 198,358	$ 154,847
Estimated Fair Value, 12 Months or More	29,579	60,844
Estimated Fair Value, Total	227,937	215,691
Unrealized Losses, Less than 12 Months	11,190	1,742
Unrealized Losses, 12 Months or More	2,675	2,259
Unrealized Losses, Total	13,865	4,001
Fixed maturity securities
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months	143,678	145,998
Estimated Fair Value, 12 Months or More	17,854	46,701
Estimated Fair Value, Total	161,532	192,699
Unrealized Losses, Less than 12 Months	6,856	1,351
Unrealized Losses, 12 Months or More	1,152	1,287
Unrealized Losses, Total	8,008	2,638
Obligations of states and political subdivisions
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months	4,479
Estimated Fair Value, Total	4,479
Unrealized Losses, Less than 12 Months	139
Unrealized Losses, Total	139
Residential mortgage-backed securities
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months	5,938	61,933
Estimated Fair Value, 12 Months or More	139	31,655
Estimated Fair Value, Total	6,077	93,588
Unrealized Losses, Less than 12 Months	27	409
Unrealized Losses, 12 Months or More	1	500
Unrealized Losses, Total	28	909
Commercial mortgage-backed securities
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months		36,398
Estimated Fair Value, 12 Months or More		866
Estimated Fair Value, Total		37,264
Unrealized Losses, Less than 12 Months		397
Unrealized Losses, Total		397
Other asset-backed securities
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months	5,407	21,281
Estimated Fair Value, 12 Months or More	8,814	462
Estimated Fair Value, Total	14,221	21,743
Unrealized Losses, Less than 12 Months	330	64
Unrealized Losses, 12 Months or More	269
Unrealized Losses, Total	599	64
Corporate and other securities
Fixed Maturity Securities
Estimated Fair Value, Less than 12 Months	127,854	26,386
Estimated Fair Value, 12 Months or More	8,901	13,718
Estimated Fair Value, Total	136,755	40,104
Unrealized Losses, Less than 12 Months	6,360	481
Unrealized Losses, 12 Months or More	882	787
Unrealized Losses, Total	7,242	1,268
Equity securities
Equity Securities
Estimated Fair Value, Less than 12 Months	54,680	8,849
Estimated Fair Value, 12 Months or More	11,725	14,143
Estimated Fair Value, Total	66,405	22,992
Unrealized Losses, Less than 12 Months	4,334	391
Unrealized Losses, 12 Months or More	1,523	972
Unrealized Losses, Total	$ 5,857	$ 1,363