Investments Maturity Distribution of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Available-for-sale Securities, Debt Maturities, Due in One Year or Less, Amortized Cost Basis	$ 23,804
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Amortized Cost Basis	126,342
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Amortized Cost Basis	98,083
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Amortized Cost Basis	458,438
Available-for-sale Debt Securities, Amortized Cost Basis	706,667	$ 667,966
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Available-for-sale Securities, Debt Maturities, Due in One Year or Less, Fair Value	24,152
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Fair Value	131,632
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Fair Value	102,448
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Fair Value	477,615
Available-for-sale Debt Securities, Fair Value	735,847
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held-to-maturity Securities, Debt Maturities, Due in One Year or Less, Amortized Cost Basis	9,357
Held-to-maturity Securities, Debt Maturities, Due After One Year Through Five Years, Amortized Cost Basis	35,383
Held-to-maturity Securities, Debt Maturities, Due After Five Years Through Ten Years, Amortized Cost Basis	48,634
Held-to-maturity Securities, Debt Maturities, Due After Ten Years, Amortized Cost Basis	154,455
Held-to-maturity Securities	247,829	224,932
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Held-to-maturity Securities, Debt Maturities, Due in One Year or Less, Fair Value	9,397
Held-to-maturity Securities, Debt Maturities, Due After One Year Through Five Years, Fair Value	37,298
Held-to-maturity Securities, Debt Maturities, Due After Five Years Through Ten Years, Fair Value	50,258
Held-to-maturity Securities, Debt Maturities, Due After Ten Years, Fair Value	157,095
Held-to-maturity Securities, Fair Value	254,048	232,891
Total Fixed maturity securities, Amortized Cost	954,496	892,898
Total Fixed Maturity Securities, Fair Value	$ 989,895	$ 940,118